Milestone 0.6.1

Committed issues (???, from 0.6.x branch):

• Fix bug in error reporting in the <x:transform /> recipe command when using the Windows MSXML implementation.
• Typo in ctools.configure handling of prefix argument.
• Platform rule matching is now case-insensitive.

Main focus of release:

• Bug fixes and minor enhancements to version 0.6
• Extend available commands, and enhancements to existing commands