Improve getTokenByRangeStart method

Do not return undefined return null instead,
aligned with other token helper methods
Add isTokenParenthesis method to token helper

This method will be helpful in future commits, meanwhile use it internally
Change signature of findOperatorByRangeStart

Add optional backward argument and change default direction
Improve requireSpaceAfterBinaryOperators rule

Add support and tests for all binary operators
Improve disallowSpaceBeforeBinaryOperators rule

Add support and tests for all binary operators
Improve requireSpaceBeforeBinaryOperators rule

Add support and tests for all binary operators
Improve disallowSpaceAfterBinaryOperators rule

Add support and tests for all binary operators
Set error pointer to the middle of entity

Add getPointerEntities method to token helper module, right now
used only inside binary rules
Make require* binary rules more consistent
Add true value as possible value for binary rules

* Add binaryOperators attribute to utils module

* Add true value as possible value to binary rules

* Add one more test for binary rules to check true value

* Update readme
"null" must be a quoted key in IE 6-8

Fixes #382
Add "unaryOperators" to utils module
Improve disallowSpaceAfterPrefixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Improve requireSpaceAfterPrefixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Add "iAndDecrementOperators" attribute to utils module
Improve disallowSpaceBeforePostfixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Improve requireSpaceBeforePostfixUnaryOperators

* Add true value

* Add more and consistent tests with binary tests
Rename property in utils module

Switch to more meaningful name
Improve defintions of operators in utils module

* Add "operators" attribute

* Don't use tmp variables for various operators definitions
Improve requireOperatorBeforeLineBreak

* Add more tests

* Add "true" as possible value for the rule