Added 1.17_R1 Support

[fierceeo]

This PR contains commits updating Slime World Manager to support 1.17_R1 and 1.16_R3 (via #179)

Other updates:

• The minecraft 1.10 dependency has been changed from paper to spigot, so it could compile on java 16.
• Project lombok has been updated from 1.18.8 to 1.18.20
• Google guava has been updated from 26.0-jre to 30.0-jre
• Travis jdk version has been updated from 8 to 16

Potential Issues:

• 1.17 needs Java 16 to compile and run, which may break compatibility with minecraft versions that do not support Java 16. (I have only tested this on minecraft versions 1.15 - 1.17)
• World height over 255 blocks may need to be implemented.

[fierceeo]

This PR now works on paper, due to a recent bug fix.
PaperMC/Paper#6079

[fierceeo]

Everything should be working now, except custom height.

[TheLimeGlass]

Can you post the compiled plugin jar, since Travis Ci won't work with 1.8 and Java 16 to automatically publish, and this pull request looking like it will never be merged.

[fierceeo]

At the moment I do not have a system with all the build tools installed.

However, here are instructions for self compiling the jar.

You will need to have the following programs installed: maven, git, wget, and java jdk.
You can download maven here: https://maven.apache.org/download.cgi
(For maven, download the Binary zip archive, extract the zip and find the mvn executable inside the bin folder.)
You can download git here: https://git-scm.com/downloads
You can download wget here (Only for windows. Macos and most linux distributions already come with it installed): http://downloads.sourceforge.net/gnuwin32/wget-1.11.4-1-bin.zip
(For wget, download that zip, extract the zip and find the wget executable inside the bin folder.)
You can download java here: https://docs.microsoft.com/en-us/java/openjdk/download

git clone https://github.com/fierceeo/SWM.git --branch feature/1.16
cd SWM
wget -O paper-1.17.jar papermc.io/api/v1/paper/1.17/latest/download && java -Dpaperclip.patchonly=true -jar paper-1.17.jar && mvn install:install-file -Dfile=cache/patched_1.17.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.17-R0.1-SNAPSHOT -Dpackaging=jar
wget -O paper-1.16.5.jar papermc.io/api/v1/paper/1.16.5/latest/download && java -Dpaperclip.patchonly=true -jar paper-1.16.5.jar && mvn install:install-file -Dfile=cache/patched_1.16.5.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.16.5-R0.1-SNAPSHOT -Dpackaging=jar
wget -O paper-1.16.2.jar papermc.io/api/v1/paper/1.16.2/latest/download && java -Dpaperclip.patchonly=true -jar paper-1.16.2.jar && mvn install:install-file -Dfile=cache/patched_1.16.2.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.16.2-R0.1-SNAPSHOT -Dpackaging=jar
wget https://cdn.getbukkit.org/spigot/spigot-1.15.1.jar && mvn install:install-file -Dfile=spigot-1.15.1.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.15.1-R0.1-SNAPSHOT -Dpackaging=jar
wget https://cdn.getbukkit.org/spigot/spigot-1.14.4.jar && mvn install:install-file -Dfile=spigot-1.14.4.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.14.4-R0.1-SNAPSHOT -Dpackaging=jar
wget -O paper-1.13.2.jar https://papermc.io/api/v1/paper/1.13.2/655/download && java -Dpaperclip.patchonly=true -jar paper-1.13.2.jar && mvn install:install-file -Dfile=cache/patched_1.13.2.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.13.2-R0.1-SNAPSHOT -Dpackaging=jar
wget https://cdn.getbukkit.org/spigot/spigot-1.13.jar && mvn install:install-file -Dfile=spigot-1.13.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.13-R0.1-SNAPSHOT -Dpackaging=jar
wget -O paper-1.12.2.jar https://papermc.io/api/v1/paper/1.12.2/1618/download && java -Dpaperclip.patchonly=true -jar paper-1.12.2.jar && mvn install:install-file -Dfile=cache/patched_1.12.2.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.12.2-R0.1-SNAPSHOT -Dpackaging=jar
wget -O paper-1.11.2.jar https://papermc.io/api/v1/paper/1.11.2/1104/download && java -Dpaperclip.patchonly=true -jar paper-1.11.2.jar && mvn install:install-file -Dfile=cache/patched_1.11.2.jar -DgroupId=com.destroystokyo.paper -DartifactId=paper -Dversion=1.11.2-R0.1-SNAPSHOT -Dpackaging=jar
wget -O spigot-1.10.2.jar https://cdn.getbukkit.org/spigot/spigot-1.10.2-R0.1-SNAPSHOT-latest.jar && mvn install:install-file -Dfile=spigot-1.10.2.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.10.2-R0.1-SNAPSHOT -Dpackaging=jar
wget -O spigot-1.9.4.jar https://cdn.getbukkit.org/spigot/spigot-1.9.4-R0.1-SNAPSHOT-latest.jar && mvn install:install-file -Dfile=spigot-1.9.4.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.9.4-R0.1-SNAPSHOT -Dpackaging=jar
wget -O spigot-1.9.jar https://cdn.getbukkit.org/spigot/spigot-1.9-R0.1-SNAPSHOT-latest.jar && mvn install:install-file -Dfile=spigot-1.9.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.9-R0.1-SNAPSHOT -Dpackaging=jar
wget -O spigot-1.8.8.jar https://cdn.getbukkit.org/spigot/spigot-1.8.8-R0.1-SNAPSHOT-latest.jar && mvn install:install-file -Dfile=spigot-1.8.8.jar -DgroupId=org.spigotmc -DartifactId=spigot -Dversion=1.8.8-R0.1-SNAPSHOT -Dpackaging=jar
mvn clean install

The classmodifier will be at the following path: slimeworldmanager-classmodifier/target/
(use the jar without the word "original-" in it. Ex: use slimeworldmanager-classmodifier-2.3.1-SNAPSHOT.jar)
The plugin will be at the following path: slimeworldmanager-plugin/target/
(again, use the jar without the word "original-")

Hope this helps.