Improved version of xsd.exe.

This version enables:

• List based collections in generated types
• Auto-capitalization of properties
• Nullable attribute types
• Removal of DebuggerStepThrough attribute

Usage: xsd2.exe <schema file> [/o:<output-directory>] [/ns:<namespace>] /all

Notes:

• PetaTest framework is used for testing.
• Original idea http://mikehadlow.blogspot.com/2007/01/writing-your-own-xsdexe.html.