[7.7.x] RHPAM-468 Improve usability and user experience when using connectors

[tiagodolphine]

[7.7.x] Improve usability and user experience when using connectors.
Cherry-pick commit 2c73d83 related to JBPM-6491.

@romartin
@LuboTerifaj

[tiagodolphine]

Jenkins execute full downstream build

[tiagodolphine]

hey @LuboTerifaj if you have a chance to review this is the cherry-pick to 7.7.x.
It will be great to merge it ASAP.

thanks !!!

[LuboTerifaj]

Hi @tiagodolphine
It seems that it works properly. Unfortunately I found issue which is also related to master. Connecting sequence flows causes that if you create these flows directly (not using activities, e.t.c., but directly sequence flows), after save, close an open the sequence flows are connected to different magnets. Specifically: source is on the right magnet and target is on the left magnet (see pictures).

Since, this is already merged in master, I am wondering whether open Jira for that, or do you want to fix it?
Thank you!

[LuboTerifaj]

Hi @tiagodolphine
Issue mentioned above is related only to sub-processes. It seems that sequence flows in main process are ok.