Add bitmap helpers

[JSCU-CNI]

This PR adds a function to convert a bitmap of free/used space into runlists.

Filesystems such as NTFS and EXTFS record which parts of the filesystem are allocated/unallocated via bitmaps where a block on the filesystem is represented by a bit. Distinguishing which parts of the filesystem are in active use and which parts are not can be useful for things like scraping.

[JSCU-CNI]

@Schamper Hopefully these changes are along the lines of what you suggested.

[Schamper]

I added some additional helpers, fixed some bugs and added some more tests. Let me know if these changes work for you or if you see any issues with them.

[JSCU-CNI]

LGTM, feel free to merge. Do you want us to update the ntfs and extfs pr's? Feel free to push the required changes (as well as other suggestions) over those branches if you want to.

[Schamper]

Do you want us to update the ntfs and extfs pr's?

If you can, that would be appreciated 😄

[codecov]

Codecov Report

❌ Patch coverage is 0% with 74 lines in your changes missing coverage. Please review.
✅ Project coverage is 0.00%. Comparing base (4d86c1b) to head (94916aa).

Files with missing lines	Patch %	Lines
dissect/util/bitmap.py	0.00%	74 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main    #127   +/-   ##
=====================================
  Coverage   0.00%   0.00%           
=====================================
  Files         28      29    +1     
  Lines       2029    2103   +74     
=====================================
- Misses      2029    2103   +74     

Flag	Coverage Δ
unittests	0.00% <0.00%> (ø)

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[codspeed-hq]

Merging this PR will improve performance by 10.27%

⚡ 1 improved benchmark
✅ 32 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	test_benchmark_lz4_decompress[python-large]	202.6 µs	183.7 µs	+10.27%

Tip

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_{Comparing JSCU-CNI:bitmap-parsing (94916aa) with main (4d86c1b)}