Fixes the sample script.
Adds a couple more tests.
Updates the grammar to include some more statements/expressions/fixes.
Changes the scripting project file to explicitly set visitor/listener to true.
Renames the Scripting project to Grammar.
Adds a Scripting project (for reals this time).
Updates the assembly info of the grammar projects.
Updates the solution file and csproj.
Fixes up the solution structure a bit.

The Scripting project should be referenced for lexer/parser specific stuff (like listeners, vistors, etc). The Grammar project will only hold the grammar file and should probably never be included as a reference for anything other than the Scripting project.