WIP: Add simple pmc collapse to replace stackcollapse-pmc.pl.

[pbmtp]

This is the start of a Rustification of stackcollapse-pmc.pl perl script.

DONE:

• basic code (i am still learning Rust so feel free to suggest modification)
• criterion bench
• compare.sh (i need to do a pull request on brendangregg/FlameGraph for a little fix and optimization for stackcollapse-pmc.pl script)
• guess code
• regression tests (guess + pmc)

TODO:

• implement kernel suffixing
• filter raw function name (address)
• symbol demangling (not done by pmcstat not for C++ nor for Rust)

[codecov]

Codecov Report

❌ Patch coverage is 90.76923% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.33%. Comparing base (9737ac7) to head (9c1945c).
⚠️ Report is 286 commits behind head on main.

Files with missing lines	Patch %	Lines
src/collapse/pmc.rs	91.20%	11 Missing ⚠️
src/collapse/guess.rs	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #214      +/-   ##
==========================================
- Coverage   89.64%   89.33%   -0.32%     
==========================================
  Files          17       18       +1     
  Lines        2357     2485     +128     
==========================================
+ Hits         2113     2220     +107     
- Misses        244      265      +21     

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