[RJA-2351][feature]: Modify existing scheduling to support recurrency.
Merge pull request #978 from ddurnev/master

[RJA-2342][fix]: Fail step execution in case of unexpected exception
[RJA-2309][feature]: Enhance scheduler- recurrence.
Added interval schedule expressions.
Merge pull request #979 from ddurnev/scheduler

[RJA-2351][feature]: Modify existing scheduling to support recurrency.
[RJA-2342][fix] - Race condition when checking agent status]
[RJA-2342][fix] - Imports cleaned
Merge pull request #980 from rsvato/bug

[RJA-2342][fix] - Race condition when checking agent status
[RJA-2381[fix]: Display jobs recurrence on UI
Store recurrence for failed jobs