[lqfb-main] Release of core v2.0.1

[Jan Behrens]

Hello developers,

last night a new version 2.0.1 of the current development line of 
LiquidFeedback Core has been released.


It contains the following changes:

- Bugfix in update script from v1.3.1 to v1.4.0
   regarding missing default for "state" column in
   "issue" table
   (updating to v2.0.1 will fix this error too)

- New table "unit_setting"

- Added column "draft_id" to table
   "direct_supporter_snapshot"

- Bugfix in function delete_private_data:
   Use "invite_code" column in member "table"
   instead of table "invite_code"

- Changed/clarified some comments


Regards
Jan Behrens