- Make customization a seperate stage of flashing.
- Gives better cancel messages
- Also cleanup CLI since adding new stages makes the stage id difficult
  to maintain.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Use 4k buffer since that seems to work much better when reading from
  sd.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Decreses sd card flashing time by 57% (only tested on Linux).
- Still slower than bb-imager but not by much.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Crates.io does not accept patched crates. So create wrapper functions
  to provide that functionality till new versions of bin_file are
  published.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Another effort to use more async
- Using try_send everywhere because frankly, no point in blocking if
  send fails. They are only progress values.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Writing to destination is now async.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Consolidate sha256 calculation helpers

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Make most of file io blocking.
- This is fine since all the file io is mostly going to run together.
- Also helps make things simpler

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Since flashing is just 1 giant copying + reading copied data, better
  to use a single spawn_blocking instead of tokio doing it internally
  for each call to fs.
- Brings the verification time down by a lot with small (~10s) impact
  while flashing

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Should ask for admin priviledge when write is clicked instead of after
  downloading.
- Also use channels instead of stream for progress.
- Since streams are lazy, they were a bottleneck in the original
  implementation.
- Shaved off 1 min from flashing.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Using buffer of 32kib now which seems to help a lot.
- Takes about half the previous time.

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

- Also add minimal iso since it is much faster to test
- Also some small UI improvements

Signed-off-by: Ayush Singh <ayush@beagleboard.org>

Some unsolved stuff
- Only linux support since I am not sure how to get removable drives on
  windows
- Need to lauch as admin.
- Verification of sd card incorect

Signed-off-by: Ayush Singh <ayush@beagleboard.org>