first release

Checkpoint 9 (#4)

* Change functionNaming check method

* Add variableNaming check

* Fix typo

* Refactor NodeVisitor and checker

* Rename files

* Refactor checkers to make them save state

* Fix typo

* Add checker template

* Add side effect checker

* Fix func name detection of FuncCall nodes

* Add selftest in travis build

* Fix exit code on error  in binary

* Refactor lint() to makeLinter()

* Add feature: fixer

* Fix typo

* Fix tests

* Refactor: make NodeVisitior call fixer, not a checker

* Add tests to variableName checker fixer

* Refactor makeLinter function interface

* Refactor: rename Checkers to Rules

* docs: lintCli function

* refactor: RulesInterface

* feature: format report in json and yaml

* feature: cli arguments --report-file and --report-format

* refactor: RulesTemplate

* feature: use external sniff rules

* fix: clear errors on getErrors

* fix

* refactor: text report template

* chore (tests) rename

* fix

* add (report) footer

* doc (README.md) add doc

* docs (composer.json) add info