[FR] Allow grouping incidents for single service

[nikolauska]

Is your feature request related to a problem? Please describe.
There are times when multiple incidents need to grouped to single hour marking. Currently I will need to manually copy summary for every incident and remove everything else other than the id.

Describe the solution you'd like
I would like a button to group incidents by service by day so I could use that to copy every incident id for single day

Example summary when grouped:
[#id1], [#id2]

Describe alternatives you've considered
There is a possibility the UI would allow selecting multiple summaries and copy ids for all of the selected ones. This would be a bigger feature than the simple grouping that I need.

[vastamaki]

I implemented a multi-select feature. By holding down CTRL + clicking incident, it will select the incident. Press "ESC" to cancel all selections. After you have selected in example 5 incidents and copy the summary, it will look like => "[#123] [#321] [#514] Currently selected incident summary"

This was way faster to implement, so I decided to do it. I will probably implement this feature in the future.