Merge pull request #388 from quamilek/release/2.1.0

Release 2.1.0 - to master
Merge branch 'master' of https://github.com/allegro/ralph_assets into develop
Merge branch 'develop' of https://github.com/allegro/ralph_assets into develop
Merge branch 'develop' of https://github.com/allegro/ralph_assets into develop
Merge branch 'develop' of https://github.com/allegro/ralph_assets into develop
simplified mode in attachments
added missing property asset_type
rm *modes* (dc,bo) from supports urls
fixed urls generation
limited asset_types to dc & bo in licences; rm opening attachments on new tab
Relations report from GUI - async version
Add doc test build to Makefile
improved redirection urls
Merge pull request #418 from quamilek/test-doc

Add doc test build to Makefile
Merge pull request #414 from xliiv/modes-in-attachments

simplified mode in attachments
Merge branch 'develop' of https://github.com/allegro/ralph_assets into develop
Merge branch 'develop' into mode-in-supports

Conflicts:
	src/ralph_assets/views/attachment.py
Review changes
updated support urls
Merge pull request #419 from xliiv/easy-mode-in-supports

Modes in supports