Module addon

Helper function to wrap a Python function into a gui.Action.
- title: string (which can contain ampersands for shortcuts)
- onTriggered: Python function that does not require arguments
- icon: optional, either an gui.Icon, or a file path to an icon image.

Helper function to wrap a Python function into a gui.Action for a context menu
- title: string (which can contain ampersands for shortcuts)
- onTriggered: Python function that does require one argument: the context selection.
- icon: optional, either an gui.Icon, or a file path to an icon image.

Search additional add-ons in searchDirs, and load them. searchDirs can be a string or list of directories. When forceEnabled is True, the new-found add-ons will be enabled regardless of the user settings.

Add-ons loaded before calling loadAdditionalAddons can influence the behaviour of this call. If a add-on by the same name but different location is already loaded, the new one will be ignored.

joins lines in a docstring where a newline appears to be in the middle
of a sentence.

It's not perfect, and the following rules apply for two lines to be joined:
- neither should be empty or all whitespace
- there should be no indentation.
- the second line should start with a letter (capital or small)