basic return rules: refactor tests

- split one big file to separate rules tests
rules api refactoring

- split rules to 2 types: node checker, and tag checker
- filter rules by tags in iterator
- filter rules by scope (now it's only function scope)
- patch rule files (set scope everywhere)
reworking jsdoc-helpers, introducing jsdoctypeparser

- remove doctrine, add jsdoctypeparser for parsing doc types
- rename jsDoc to jsdoc for simplicity
- rename forEachTag to iterate
- remove data property, extend DocComment object
- simplify param checkers

Fixes #3
checkReturnTypes: add 'class' as valid custom object

Fixes #32
checkRedundantReturns: add test for issue #34
split param tests to separated files (for simplicity)

- add basic tests for configuring with empty data
- add configure and check helpers to tester
- change mocha reporter to dot
tests: fix linting directories to lib and test
checkTypes: split rule logic and add checkin for other typed tags
fix location issues in jsdoc and split param rules

- create DocLocation class with line and column
- add loc field to DocType, DocName and DocTag
- split params to several files
- add tests for jsdoc classes
split returns to separated rules
Merge pull request #27 from zxqfox/feature/param-return-refactoring

A lot of refactoring, add tests, migrate to jsdoctypeparser