Added:
- sequence numbers
- better filtering for image encapsulated data messages versus FTP
- directory list now contains file sizes
- open command now returns file size in data

SLUGS has maintained their patches out-of-tree for a long while now.
These will eventually get merged back in, but it'll be easier to evaluate them as fresh commits instead of modifications to this old & dead code, so we'll delete this for now.

Also added selection from tree view for downloading

Also modified protocol to better support eof’s on list and read
commands.

These changes prevent random encapsulated data packets as being thought
to be images.

Also changes for Ack timeouts and unit testing

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

Most math and backend storage was floats anyways, so most of these changes just half the data copied during function calls without reducing precision.

Otherwise MANUAL_CONTROL messages are still sent at the regular 50Hz. This reduces transmission bandwidth from 0.9kbps when the joystick is used continuously to 0.1kbps when it's idle.
To prevent possible issues from the last high-bandwidth message being lost and the system then not responding for .1s, the last messsage is double-transmit which should prevent those issues.