Update DG

[tayruxin]

• add planned enhancement
• add manual testing
• edit activity diagram

[codecov[bot]]

Codecov Report

Merging #271 (8a19048) into master (2f833d1) will increase coverage by 0.13%. Report is 5 commits behind head on master. The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #271      +/-   ##
============================================
+ Coverage     74.18%   74.31%   +0.13%     
- Complexity      578      579       +1     
============================================
  Files            88       88              
  Lines          1898     1896       -2     
  Branches        220      220              
============================================
+ Hits           1408     1409       +1     
+ Misses          409      407       -2     
+ Partials         81       80       -1     

see 3 files with indirect coverage changes