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