Extract separate shoes-highlighter gem

Update the help system to use the new location.
Necessary gemspec to build shoe-highlighter
Bundler support required by new file structure

Previously our separate 'gems' have worked fine from source simply
because they're all in the lib folder together. Changing that to be
split into separate gem directories actually breaks things unless we get
Bundler into the mix to get our proper load paths set.
LICENSE and README tweaks for new gem
In development use by path, not gemspec

Travis didn't seem happy with it by gemspec and tried to install from Rubygems.
Fix for using shoes-highlighter by path

Was the relative pathing in gemspec that was problematic
Add modal windowing

Adds style to Shoes.app calls for making things modal.

Also supports a #wait_until_closed so we can hold until we get an answer
for model dialogs.
Shoes-based implementation of ask dialog
Don't need that old SWT ask anymore
Revising version number on shoes-highlighter

Will eventually be independent from main Shoes, so treat it as such.
More common way to reference local gem by path
Merge pull request #939 from shoes/shoes_ask

Better input sizing on ask dialog

* Changelog: improvement
* Replaces the SWT implementation with a shoes implementation, better reusability but might give us headaches down the road through multi app, let's see :)
Farewell, ruby-shoes!

With our new gem structure, bin/ruby-shoes is no longer supported.

bin/shoes-swt is the replacement, and has the necessary code to work
with the changes we're making to gem layout. Additional backends in the
future will be responsible for adding their own executables as well.
Merge pull request #937 from shoes/shoes-highlighter

Introduce shoes-highlighter gem

Fixes #257 and #934

Changelog: feature
GTK3 on my new machines apparently needs even more wiggle room for gutter (14)
introduce rubocop
Basic rubocop configuration
Disable a couple of cops for string and hash style
Through rubocop #1410 the Java::float problem was fixed
Comment our method name exception back in