Changeset 8975

#1985:

• Moved arithmetic progression dialog to MainForm (created a folder dialogs)
• Added a button to generate such a progression for snapshot times
• Changed TimeLimitRun to react on ExecutionTimeChanged instead of maintaining its own timers
• Changed to allow manual snapshoting only during Paused state
• Perform a pause + snapshot when terminating the algorithm instead of stop + snapshot (allows the algorithm in the final snapshot to continue running if the option was selected)