Add license and copyright text to readme.
Change lgpl badge to smaller one and move to same line as title
Introduce devtools to provide convenient rake tasks.
Override metrics:coverage task to make it always #execute unit specs
Get flay, rubocop and coverage past CI
Switch to exbinary/devtools.

Waiting on upstream to merge coverage and flog task changes.
Merge branch 'devtools'

Conflicts:
	README.md
Extract IndentAware mixin out of TextUtils and include in Entry.
Rename TextUtils to StringHelpers, move to helpers.rb
Refactor some minor smells in Parser
Add #type to Entry-like classes, simplify EntryContainer#type?
Introduce EntryPair to help refactor, simplify parsing.
Adjust flog, flay, reek, coverage config.