validateIndentation: handle breakless case stmts

Fixes #693
Parsing: Use the harmony parser via the esnext flag in the config

Closes gh-692
Fixes #691
Prepare for version 1.7.3
1.7.3
Readme: remove duplicative example for requireCurlyBraces
New rule: requireSpaceBeforeKeywords
New rule: disallowSpaceBeforeKeywords

Closes gh-699
Correct error message for "requireSpaceAfterKeywords" rule
StringChecker: Comment typo

Closes gh-702
Parsing: Follow up test for multiple checks using the esnext config flag

Closes gh-694
requireSpaceAfterLineComment: add "except" option

* According to #592 and #593 it was decided to make "except" option for
  this rule to pass list of allowed characters

* Treat tabs as spaces in comments

Closes #696
Fixes #592
Docs: Clarify "config" option

Closes #675
Package "separated-coverage" was renamed to "unit-coverage".
disallowSpaceBeforeKeywords: Fix assertion typo

Closes gh-713
disallowSpacesInAnonymousFunctionExpression: set correct error pointer

Fixes #714
Remove mocha's "only" call
disallowDanglingUnderscores: add "super_" to allowed identifier list

Closes gh-717
Fixes #715
Preset: remove "disallowMultipleLineBreaks" rule from crockford preset

Fixes #718
validateParameterSeparator: fix for multiple spaces between parameters

When there are multiple spaces between parameters, throw an error
until it matches the specified seperator value.

Fixes #701
Closes #707
New Rules: (require | disallow)PaddingNewlinesBeforeKeywords