The GUI should be responsive when syncing a lot of files

Issue

The GUI is not responsive when synced a lot of files.
I think this is the amount of work needed to update the transfered files list in the systray menu.

Ideas

• Actions about not chunked transfers could be hidden from the systray. This would reduce the amount of calls to the function that refreshes the ongoing transfers. When the transfer is finished, the item in the systray would be visible as usual.
• Do not add not chunked transfers into the database.
• Investigate calls to QMLDriveApi.get_syncing_count() and when the value does not change between 2 calls, do nothing.