dotPageMod v0.5 – Ready or not, run!

The first release in more than five years makes Python 3 usage in the app official (after more than 3 years in git), does the usual amount of changes to the examples and implements two minor features:

1. It is now possible to insert script earlier/later than the default at readyState interactive (document_end) based on the ending of the filename (e.g. .start.js for document_start).
2. Showing an error message in on hover in the panel as well as in the web console of the tab if a script fails, which was previously just shown by a red highlight in the panel