Add support for older Puppet versions

[Garagoth]

Hi!

Had to add some tweaks to allow this provider to work on PE 2.8.x
If it passes your tests, could you please merge?

Regards,
Garagoth.

[carlossg]

you would need to fix the tests too

  1) Puppet::Type::Maven::ProviderMvn#ensure= with ensure => present given a valid path when mvn returns 1 with no output
     Failure/Error: let(:output) { Puppet::Util::Execution::ProcessOutput.new '', 1 }
     NameError:
       uninitialized constant Puppet::Util::Execution::ProcessOutput
     # ./spec/unit/puppet/provider/maven/mvn_spec.rb:204:in `block (7 levels) in <top (required)>'
     # ./spec/unit/puppet/provider/maven/mvn_spec.rb:207:in `block (7 levels) in <top (required)>'

  2) Puppet::Type::Maven::ProviderMvn#ensure= with ensure => present given a valid path when mvn returns 1 with output "busted!"
     Failure/Error: let(:output) { Puppet::Util::Execution::ProcessOutput. new 'busted!', 1 }
     NameError:
       uninitialized constant Puppet::Util::Execution::ProcessOutput
     # ./spec/unit/puppet/provider/maven/mvn_spec.rb:213:in `block (7 levels) in <top (required)>'
     # ./spec/unit/puppet/provider/maven/mvn_spec.rb:217:in `block (7 levels) in <top (required)>'

[carlossg]

Version v1.1.11 should work with puppet < 3.4.0

[carlossg]

the change was introduced in #31

[Garagoth]

#31 does not fix this. Let me fix those tests then, somehow I missed them.
EDIT: Uh, this requires to write new set of tests for Puppet that does not have Puppet::Util::Execution.
Currently I have no resources to do this, I'm sorry. Will try to get back to it then work permits.

[saliceti]

I am interested as well because I am stuck with 2.7.3 right now.