Remove --full flag

[manuyavuz]

After the improvements in #8 merged completely, I think we can get rid of --full flag because it would give answer in less than a second in most cases.

[manuyavuz]

@orta We thought about removing --full flag, but I have a small concern.

non-git repositories still won't utilize improvements presented. Their search will still be slow.

However, I do think we can still move --full as default option because I assume users using non-git repos will be much minority.

What about adding a new flag like --simple and moving --full algorithm to default option?

cc: @alloy @floere @segiddins

[segiddins]

Sounds good to me!

[orta]

Yeah, that's cool for me too

[manuyavuz]

Good then.