Extend modal area to support user input (e.g. change owner, reassign to project)

[apyrgio]

The discussed steps are the followed:

• Break action modal in three types: plain, contact, transfer ownership (needs better name) (@apyrgio)
• Add optional confirmation step based on caution level. (@apyrgio)
• For transfer ownership scenarios, add the following table (@athinab):

From	To
id1	<input1>
id2	<input2>

As one can see in the above multiple action scenario, the ownership can be transfered to different entities for each item.

• Send list with to - from pairs (@athinab)
• Change the server code to recognize the to - from format (@apyrgio)
• Add the appropriate error messages for this operation (@apyrgio)

[apyrgio]

Also, note that once the above is implemented, we can move to something like this:

From	To	button
id1	<input1>	<button>
id2	<input2>	<button>

which will utilize our existing DataTables implementation. The concept is the following:

• When the user presses a row button, a new table will appear. This table will be the corresponding DataTable for the item category that the user must choose from (e.g. in "Reassign to Project", the corresponding table will be the Projects list).
• Once the user chooses an item from the table, its id will be added in the input box.
• Optionally, the same id can be added to the rest of the boxes, but that's something to think of later.