enable the ruby concat script on Solaris

Per discussion on #174, Solaris 10 does not support the find/xargs
switches that were introduced in that PR (but Solaris 11 does).

+ add a shebang to concatfragments.rb
+ fix linter warnings/errors
Merge pull request #186 from jhoblitt/feature/rb_concat_solaris

enable the ruby concat script on Solaris
Validate the concat::fragment order parameter as string||integer

This is to work around a validation issue that arises under the 3.x future
parser, as proper numeric types have been introduced (ie, not all scalar values
are strings).  Users have come to expect to to be able to pass in unquoted
integer values to the order parameter which will fail to validate as a string
when the future parser is enabled.
raise the "low bar" travis puppet version to 2.7.6

It appears that puppet 2.7.3 does not play nicely with stdlib 4.2.0.
add .vagrant to .gitignore