Fix/general cleanup

[jrchamp]

Hi rtCamp team,

I was looking at this plugin for a lightweight Google login option. A quick review highlighted a few issues such as extract(), template variable naming and some leftover mentions of the 'github login' plugin that this plugin sourced.

In reviewing similar PRs, it looks like someone else was concerned about extract(). The benefit of this new PR is that it aligns with WordPress Coding standards, but please do credit them for their work.

Fixes #260
Fixes #267

There are quite a few PHPCS issues, but I did not want "fix" them all without asking first because you may be using a different coding standard:

• Generic.Classes.OpeningBraceSameLine.BraceOnNewLine (1)
• Generic.CodeAnalysis.UnusedFunctionParameter.FoundAfterLastUsed (3)
• Generic.Commenting.DocComment.LongNotCapital (1)
• Generic.Commenting.DocComment.MissingShort (98)
• Generic.Commenting.DocComment.SpacingBeforeTags (1)
• Generic.Formatting.MultipleStatementAlignment.IncorrectWarning (2)
• Generic.Formatting.MultipleStatementAlignment.NotSameWarning (16)
• Generic.Functions.OpeningFunctionBraceKernighanRitchie.BraceOnNewLine (3)
• Generic.WhiteSpace.DisallowSpaceIndent.SpacesUsed (102)
• Generic.WhiteSpace.ScopeIndent.IncorrectExact (2)
• NormalizedArrays.Arrays.ArrayBraceSpacing.SpaceAfterArrayOpenerSingleLine (5)
• NormalizedArrays.Arrays.ArrayBraceSpacing.SpaceBeforeArrayCloserSingleLine (5)
• NormalizedArrays.Arrays.CommaAfterLast.MissingMultiLine (78)
• PEAR.Functions.FunctionCallSignature.CloseBracketLine (3)
• PEAR.Functions.FunctionCallSignature.ContentAfterOpenBracket (3)
• PEAR.Functions.FunctionCallSignature.MultipleArguments (1)
• PEAR.Functions.FunctionCallSignature.OpeningIndent (1)
• PEAR.Functions.FunctionCallSignature.SpaceAfterOpenBracket (29)
• PEAR.Functions.FunctionCallSignature.SpaceBeforeCloseBracket (30)
• PSR2.Classes.ClassDeclaration.CloseBraceAfterBody (1)
• PSR2.Classes.ClassDeclaration.SpaceBeforeName (1)
• PSR2.Files.EndFileNewline.TooMany (1)
• Squiz.Commenting.FileComment.Missing (1)
• Squiz.Commenting.FileComment.MissingPackageTag (13)
• Squiz.Commenting.FileComment.SpacingAfterComment (2)
• Squiz.Commenting.FunctionComment.EmptyThrows (1)
• Squiz.Commenting.FunctionComment.MissingParamComment (12)
• Squiz.Commenting.FunctionComment.MissingParamTag (1)
• Squiz.Commenting.FunctionComment.ParamNameNoMatch (1)
• Squiz.Commenting.FunctionComment.SpacingAfterParamType (7)
• Squiz.ControlStructures.ControlSignature.SpaceAfterKeyword (1)
• Squiz.Functions.FunctionDeclarationArgumentSpacing.SpacingAfterOpen (1)
• Squiz.Functions.FunctionDeclarationArgumentSpacing.SpacingBeforeClose (1)
• Squiz.Functions.MultiLineFunctionDeclaration.SpaceAfterFunction (9)
• Squiz.Operators.ValidLogicalOperators.NotAllowed (2)
• Squiz.WhiteSpace.SuperfluousWhitespace.EmptyLines (7)
• Universal.Arrays.DisallowShortArraySyntax.Found (347)
• Universal.NamingConventions.NoReservedKeywordParameterNames.classFound (2)
• Universal.NamingConventions.NoReservedKeywordParameterNames.objectFound (5)
• Universal.NamingConventions.NoReservedKeywordParameterNames.returnFound (1)
• Universal.WhiteSpace.PrecisionAlignment.Found (45)
• WordPress.Files.FileName.InvalidClassFileName (23)
• WordPress.Files.FileName.NotHyphenatedLowercase (26)
• WordPress.NamingConventions.ValidHookName.UseUnderscores (17)
• WordPress.NamingConventions.ValidVariableName.PropertyNotSnakeCase (11)
• WordPress.NamingConventions.ValidVariableName.UsedPropertyNotSnakeCase (68)
• WordPress.NamingConventions.ValidVariableName.VariableNotSnakeCase (97)
• WordPress.WhiteSpace.ControlStructureSpacing.NoSpaceAfterOpenParenthesis (3)
• WordPress.WhiteSpace.ControlStructureSpacing.NoSpaceBeforeCloseParenthesis (3)
• WordPress.WhiteSpace.OperatorSpacing.NoSpaceAfter (32)
• WordPress.WhiteSpace.OperatorSpacing.NoSpaceBefore (30)