BRANCH 4.1:
  - added screenshot of sameple_02 theme
  - fixed a bug in Create Project Wizard in the Theme selection UI for Tactic TEAM
BRANCH 4.1:
   - fixed Sqlite implementation of process_value of timestamp column type to fix the bug in insert with auto CURRENT_TIMESTAMP value
   - fixed the bug of Sqlite implementation of nullable by properly detecting the NOT NULL constraint and avoided
     error messages when inserting new items
Merge branch '4.1' of https://github.com/Southpaw-TACTIC/TACTIC into 4.1