(maint) Add comment json support

Prior to this commit, gatling-puppet-load-test did not have comment
support for Jenkins job configuration (say, in case you didn't want to
install PE every single time you ran a job). This commit changes that by
doing a quick pass through the given config file to remove any lines
that are commented out.
(maint) Refactor Json Remove Comment

This commit refactors the removing comment functionality by renaming the
method, removing unused variables and using some fancy build in string
methods for checking if a line starts with # or //.
Merge pull request #60 from briancain/maint/master/json_comment_support

(maint) Add comment json support