Refactor some local helper functions
Decrease code redundancy for handling left clicks
More consistent comma style (at end of collection)
Fix some style issues (detected by flake8)
Remove *Contributors* section from man page

Not really helpful. The contributors can be seen from the VCS or the
CONTRIBUTORS file in the repository, if desired.
Add @moredread to contributors
Move unhelpful references from MAN page to README

While these links come in handy for developers they are not useful for
the average user.
Remove DEPENDENCIES section from man page

The dependencies should already be installed, when you have the man page
installed (which is probably via your distribution repository).
Furthermore, this section is redundant and hard to keep in sync with the
listing in README.
Reword some sections of README/man page
Merge branch 'clean-doc'
Merge branch 'fix-style-issues'