* Added a bunch of RSpec 3 snippets (Thanks @ronny)
* Source / Spec switching (fast-and-precise mode) now supports structure like
  - lib/path/to/code.rb
  - spec/lib/path/to/code_spec.rb

  * previously fast-and-precise mode only supports
    - lib/path/to/code.rb
    - spec/path/to/code_spec.rb
    and
    - app/path/to/code.rb
    - spec/path/to/code_spec.rb
  * note: now for "lib", the spec folder may or may not contain nesting "lib"
    - when having a "lib" folder in your project
    - you would have "spec/lib/..." if it's Rails, and "spec/..." if it's Gem
