Fix random failure of interruption specs

The specs were actually feature tests rather than unit tests.
Furthermore testing with threads was the cause of the random failure.
So I've broken down them to real unit tests.
Merge pull request #238 from yujinakayama/fix-interruption-spec

Fix random failure of interruption specs
Remove Syntax cop and use Parser's diagnostic engine instead.
Continue with inspections after syntax errors when possible.
Merge pull request #237 from jonas054/syntax_check_by_parser

Syntax check by parser
improved string quotes regex + fixed one pending test
Merge pull request #242 from ranmrdrakono/string_literals_patch

improved string quotes regex + fixed one pending test
Update changelog
Fix off-by-one error in favor_modifier.

This was corrected earlier, but I didn't get it quite right that time.
There were instances when IfUnlessModifier reported a violation, but
fixing the violation would make the line too long.

Conflicts:
	CHANGELOG.md
Merge pull request #241 from jonas054/fix_favor_modifier_again

Fix off-by-one error in favor_modifier.
Recognize a line with CR+LF as a blank line in AccessControl cop.
Merge pull request #244 from jonas054/fix_access_control_on_windows

Recognize a line with CR+LF as a blank line in AccessControl cop.
Handle multiple constant assignment in ConstantName cop.
Merge pull request #245 from jonas054/fix_constant_name_bug

Handle multiple constant assignment in ConstantName cop.
Add verbose version display (fixes #236)
Add support for Rails-specific cops (fixes #224)
Add `-r` shorthand for `--require`