also: remove mailing list and irc channel address from development docs,
it is enough to have this information on the main page and on the support page.
link to the locations of different tools when I know them. i marked
the ones I don't know about specially so we can document those as
well.
point to the Github releases for the standalone binaries upload
we stop supporting them, because there are better alternatives:
- use a distribution package (from your linux distribution), if available
- use a pyinstaller binary provided by us (they include all you need in 1 file and
thus have better compatibility properties and are easier to install than a wheel)
- install from source (pypi or git) if everything else fails
README.rst (shown on github and also at the start of the html docs) shall
be like an elevator speech - convince readers in a very short time.
this is most important, everything else can come after we got the reader's interest.
include README into docs to avoid duplication.
also include CHANGES into docs.
add developer docs, move examples from tox.ini there
add separate support docs
remove glossary, most of what was there can be understood by an admin from context
move attic and compatibility note to the end
