Better CLI implementation

[JakeStanger]

The current CLI is fine, but the need to be in the current directory for some operations is a little annoying. The current implementation also makes it difficult to expand for more features (such as the WatchConfig fields added in #49 ).

I would suggest initially migrating the current code to use Clap or similar.

Commands could then be updated to the something like the below format:

dura serve # can be left as-is

# these default to cwd
dura watch [dir] [--include <includes>] [--exclude <excludes>] [--max-depth <depth>]
dura unwatch [dir]
dura capture [dir]

[tkellogg]

Definitely. This would be a huge improvement.

[drupol]

Working on clap integration, working fine so far.

[tkellogg]

@JakeStanger does this resolve the issue adequately?

[JakeStanger]

Absolutely, that's fantastic service! Awesome and very speedy work @drupol

[drupol]

Thanks! It's the second time I do a PR for a rust project, I really like it !