Remove trailing whitespace

  via: sed -i 's/ $//g' `grep -rl " $" lib test`
Clean up double quotes in gemspec
Fix Lint/DefEndAlignment
Redundant to_s
rubocop/pre-commit
Style/EmptyLines
Style/HashSyntax
Style/StringLiterals
Style/ColonMethodCall
Style/EmptyLinesAroundBody
Style/TrailingBlankLines
Style/EmptyLinesAroundAccessModifier
Style/SpaceAfterComma
Style/SpaceAroundOperators
Style/SpaceAroundEqualsInParameterDefault
Style/LeadingCommentSpace
Style/RedundantSelf
Identing
Style/TrailingWhitespace
Refactor long lines