Replace our home made background scheduler with apscheduler.

* Remove Debian Stretch build
* Drop support of jinja2<2.10
* Drop support of cherrypy<8.9.1

Since 6.0, setuptools_scm only support python>=3.6

* Replace argparse by configargparse
* Allow configuration to be define using environment variable
* Allow configuration to be splitted in multiple files
/etc/rdiffweb/rdw.conf.d/*.conf
* Remove obsolete `rdiffweb` file used to define repository encoding
* Update man page

* Add humanfriendly as dependencies
* Provide a CherrpyForm to support WTForm with cherrpy
* Add SizeField to get/set humanfriendly quota value
* Use humanfriendly everywhere applicable for file size

Force long_description format to markdown

Patrik Dufresne authored Sep 21, 2020 and Daniel Baumann committed Oct 14, 2020

Translation catalogues should be updated only when translation files are
updated.

Translation catalogues should be updated only when translation files are
updated.

Replace all URL patrikduresne.com by ikus-soft.com. Remove all reference
of Github to make reference to Gitlab.

Add a new settings at the user level to define the user's role. Admin,
Maintainer and User. Admin are allowed to do everything. Maintainer are
allow to browse and delete repo. User are only allowed to browse.

Sqlite3 is part of python>2.7. Remove any dependencies or references to
pysqlite2.

Create a new independent command line entry point `rdiffweb-restore` to
restore the data directly into an archive. This entry point may be
called to offload the processing from the main threads.

Along these changes, also fix all the encoding issues related to
restoration for CentOS 7 (python 3.6) by using PAX format.

Also support rdiff-backup2.

The pipeline is failing very often because of network issue. To reduce
failure and reduce the download time, let point pip to our pip-proxy.

To avoid regression based on Jinja version add it to Tox environment
list. Also add job for them in gitlab pipeline

To reduce the page footprint and to reuse the same code base, create new
macro to delete confirm deletion.

With this new api, also reffactor to have a single object to manipulate
RdiffRepo in database and on disk.

We need to use latest pip version to pick the right version of pacakges
for py27. Otherwise, pip will install python 3 only packages into a
python 2.7 environment.

Move all the ssh key management into the UserObj to support database
storage.