1.2.0: Merge pull request #15 from msarahan/no_more_bat_wrappers

This release runs python and pythonw script types in python shells that set PATH for environments, rather than bat files.

This release also changes the "scriptargument" key to "scriptarguments" and expects a list of arguments to be passed to the command. The older syntax was a space-delimited string, and was not consistent between "script" and "system" shortcut types.