Merge remote-tracking branch 'origin/bindings' into bindings

Conflicts:
	src/Markup/Perspex.Markup/Binding/ExpressionNodeBuilder.cs
	tests/Perspex.Markup.UnitTests/Binding/ExpressionNodeBuilderTests.cs

src/Markup/Perspex.Markup/Perspex.Markup.csproj

@@ -48,7 +48,9 @@
     <Compile Include="Parsers\CSharp\ExpressionStatementSyntax.cs" />
     <Compile Include="Parsers\CSharp\Grammar\ExpressionGrammar.cs" />
     <Compile Include="Parsers\CSharp\Grammar\IdentifierGrammar.cs" />
+    <Compile Include="Parsers\CSharp\Grammar\LiteralGrammar.cs" />
     <Compile Include="Parsers\CSharp\IdentifierSyntax.cs" />
+    <Compile Include="Parsers\CSharp\LiteralExpressionSyntax.cs" />
     <Compile Include="Parsers\CSharp\MemberAccessExpressionSyntax.cs" />
     <Compile Include="Parsers\CSharp\PrefixUnaryExpressionSyntax.cs" />
     <Compile Include="Parsers\CSharp\SyntaxKind.cs" />