Added an app.config to all projects to redirect uses of FSharp.Core 4.0.0.0 to FSharp.Core 4.3.0.0. This fixes the issues where fsharplex/fsharpyacc were crashing when running the test cases via NUnit on some machines.
Removed unused 'defaultStackCapacity' constant.
Implemented Set<char> equivalence tests for CharSet with FsCheck.
Implemented some of the unit tests for the CharSet module.