(maint) No longer necessary to gem install rgen

Puppet used to express gem dependencies on rgen in its Gemfile, packaging,
etc, but in PUP-2914 the rgen code was vendored into puppet, and the
dependencies removed.

However, the future parser setup step still tried to install the rgen
gem, but only when testing against git checkouts (effectively Solaris
and Windows).

Since rgen is vendored in puppet, it is not necessary to install the gem
during future parser testing.
Merge pull request #3365 from joshcooper/maint/stable/remove-rgen-install

(maint) No longer necessary to gem install rgen
(maint,QENG-174) Allow installing a new puppet package on top of the PE tar

Currently, when running the puppet acceptance tests against PE, you
can only test the version of puppet that is shipped with the PE
tarball. This adds another step to the PE pre-suite which will install
an arbitrary version of pe-puppet on top of the installed PE tarball.
Merge pull request #3366 from branan/QENG-174

(maint,QENG-174) Allow installing a new puppet package on top of the PE tar
(PUP-3479) (PUP-3737) Update Windows ffi ~> 1.9.5

Ruby 2.1.3 on Windows requires ffi 1.9.5. Update our Windows dependencies
to allow 1.9.5+ to be selected.

This commit was originally merged to the master branch targeted at 4.x,
when it should have been targeted first at the stable branch to affect
the 3.7.x release and keep it in sync with Facter 2.3.0, which now
requires ffi ~> 1.9.5

Gem installation of Puppet on Windows is thus currently broken until
Puppet 3.7.4 ships or a workaround is employed, where Facter 2.2.0 is
installed by gem prior to installing Puppet.
Merge pull request #3378 from Iristyle/ticket/stable/PUP-3479-update-FFI-dependency-1.9.5

(PUP-3479) (PUP-3737) Update Windows ffi ~> 1.9.5
(PUP-3728) Fix off by one error in cron month names

When a name, such as "January", is used to specify a month in the Cron type,
the resulting numeric value would be off by one (i.e. "0"). This is because
month is unique among "namable" crotab entries in that it does not use 0-based
indexing. This patch updates the spec tests to enforce this expectation and
fixes the issue by padding out the list of acceptable month names so that
indices start at 1.
Merge pull request #3380 from Sharpie/PUP-3728-fix-cron-monthnames

(PUP-3728) Fix off by one error in cron month names