Add option to disable output buffering

[clubby789]

Description/Motivation/Screenshots

Closes #910
Allows disabling Gef's internal buffer, which can improve usage of long-running commands (such as #906).

Against which architecture was this tested ?

"Tested" indicates that the PR works and the unit test (see docs/testing.md) run passes without issue.

• x86-32
• x86-64
• ARM
• AARCH64
• MIPS
• POWERPC
• SPARC
• RISC-V

Checklist

• My PR was done against the dev branch, not main.
• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• If my change adds new code, adequate tests have been added.
• I have read and agree to the CONTRIBUTING document.

[Grazfather]

This looks fine to me. Should probably be documented with the rest of the config.

[clubby789]

What's the right place to document config? I had a brief look but only saw the description in GefSetting in GEF itself

[Grazfather]

Yeah, I guess we don't document each setting, but if we did, it would go here

[hugsy]

What's the right place to document config? I had a brief look but only saw the description in GefSetting in GEF itself

Don't bother creating docs for GefSetting. I already have a branch where I generate them automatically. I'll merge that eventually.

[hugsy]

Took 2sec to squash merge the branch. Settings are now in the docs (see https://hugsy.github.io/gef/settings/context/)