Context operators for adjusting context values directly to avoid adding operators...

Context operators for adjusting context values directly to avoid adding operators for adjusting single values which also need duplicate notifiers.

wm.context_set(path="scene.tool_settings.someattr", somevalue)
wm.context_toggle(path="scene.tool_settings.somebool")
wm.context_toggle_values(path="scene.tool_settings.some_enum", value_1="somevalue", value_2="othervalue") # switch between 2 values
wm.context_cycle_enum(path="scene.tool_settings.some_enum", reverse=False)

the path value is taken from the context so the full path is
context.scene.tool_settings...

This means in keymaps you can cycle draw modes, change PET- anything with rna access.
If its not so nice to map keys to operators like wm.context_set we could use macro's to wrap it and have its own name

Use this for PET and setting pivot options

- Made userpref key shortcut Ctrl+Alt+U since its not used in 2.4x
- added pivot_point_align (Alt+Comma)
- added PET wasnt rna wrapped correctly.