Simplify markup of examples for ease of editing
Add a document on nested :describe
Add a document on :context
Add tests on nested :describe
Treat :context as an alias of :describe
Recognize nested :describe
Support to refer a parent suite
Run nested :before/:after blocks properly
Refactor - Introduce s:suite.pretty_subject
Show nested :describe subjects in a pretty format
Add tests on :context highlighting
Support syntax highlighting for :context
Add tests on indentation about nested :describe
Indent also :context properly
Merge branch 'support-nested-describe'

Close gh-36.
Add release notes on 1.4.0
Bump up version to 1.4.0
Merge branch 'prepare-1.4.0'