Allow specifying how many frames to pull in when creating a bucket

[pyoor]

When creating a new bucket, it would be nice to specify how many frames to pull in from the initial crash to create the signature. Often times stacks in rust bugs have a lot of common code at the top of the stack.

[jschwartzentruber]

There are a number of hidden URL parameters to /crashmanager/signatures/new/ we should expose in UI:

stackframes=int
forcecrashaddress=0, 1
forcecrashinstruction=0, 1

Regarding Rust backtraces, if you see patterns to the common code in your crashes, you can add a rule here to increase the default: https://github.com/MozillaSecurity/FuzzManager/blob/8143bf25d41a05f105a336bc9b7e07112954f5ae/server/crashmanager/views.py#L421-L426