add readme and changelog to long-description

reformat changelog in .rst
add downloads link; mention windows support
Merge remote-tracking branch 'kali/improve-long-description' into develop
Update apt-get dependencies

* Also, tweak different sections to be consistent with the
  new quickstart.
* Squashed contributions by Jeremy (@bneg)
* add note about authors.rst
add include to testing howto too
Fixes to environment.rst. Closes: #4185
add prompt indication for the virtualenv
add pip install
Merge remote-tracking branch 'kali/feature/quickstart-and-deps' into develop
use coloredlogs optionally
Mail State Machine refactor. Closes: #4059
changes file
Merge remote-tracking branch 'kali/feature/refactor-mail-connections' into develop
dependency pinning on requests
Use unicode values and encode them out.
Encode cert path before send it.
Adds a command to freeze debian versions.
Merge remote-tracking branch 'kali/pin-requests-dep' into develop
Merge remote-tracking branch 'kali/feature/freeze_debianver_command' into develop
Encode paths before use them.