Update nlcst-to-string
Move spec to new `test` directory
Update .gitignore, .npmignore, bower ignore
Move build-expressions script to `script/`
Refactor benchmark
Refactor Readme.md
Add NLCST to package keywords
Refactor indent in .jscs.json
Add script to generate fixtures
Remove source node creation from parser

This task should be deferred to other tools.

Additionally, this adds `makeInitialWhiteSpaceSiblings` to
paragraph modifiers.
Refactor test

- Refactor spec to be more readable;
- Add nlcst-test as a dev-dependency to validate NLCST
  output;
- Move NLCST results from test file to `fixture` directory;
- Add chalk and diff as dependencies, to show differences
  between a fixture and the actual output on errors.
Remove apostrophe from initial word-punctuation

The apostrophe at the beginning of a line does not share the
same meaning (elision) in every Latin-script language.
Remove extraneous istanbul ignore
Update changelog for 0.2.0-rc.3
0.2.0-rc.3