Generate the right wiki links.
Improve and refactor ControlParameter

- Make detector concentrate on use of parameter as a value. Using the
  result of a method call involving the parameter is considered
  legitimate use. Comparing to a value is not.
- Handle edge cases like use of if inside a condition
- Re-format specs
- Refactor smell detector
Merge pull request #309 from troessner/refactor-control-parameter

Improve and refactor ControlParameter
Simplify NestedIterators detector
Merge pull request #311 from troessner/generate-the-right-wiki-links

Generate the right wiki links.
Merge pull request #310 from troessner/refactor-nested-iterators

Simplify NestedIterators detector
Bump version to 1.4.0.
Revamp README.
Merge pull request #316 from troessner/revamp-README

Revamp README.
Remove use of rubygems
Merge pull request #317 from troessner/remove-rubygems

Remove use of rubygems from env.rb
Depend on parser and unparser instead of ruby_parser and friends

To avoid confusion, removes flay from the deps.
Make source_code specs pass
Make more specs pass

- Use custom node classes, mapped by type
- Re-implements #s to use these classes
- Start modifying node classes and type symbols to match new AST format
Make sexp_extensions_spec pass
Make sexp_formatter_spec pass
Remove unused TreeDresser
Make code_context_spec pass
Replace :defn with :def
Make method_context_spec pass