* Remove unused development dependency on open4
* Use pessimistic versioning for coderay, rake, and simplecov
* Bump versions of rake and mocha
* Loosen pessimistic versioning on mocha and bond
The only remaining warning from RubyGems is on coderay -- we chose not
to use '~> 1.1' because there were breaking changes between 1.0 and 1.1.
'openstruct' is not a runtime dependency that pry has anymore but it
was not added to the changelog. other two changes include better messages
for older changelog entries related to config.
* Make it Markdown instead of plain text
* Clean up wording and formatting back to 0.9.0
* Incorporate entries for non-master releases 0.9.11.4 through 0.9.12.2