Minor cleanups of readme files

[cijothomas]

Towards #1306

1. Consistent readme for more crates.
2. Moved releasing.md file to under scrips directory. This is only intended for maintainers, and this will keep the top level leaner.
3. Fix some jaeger cleanup leftovers.
4. Nit doc fixes.
   (not fully sure of the current content of readme.md files. Will revisit once more before next release to ensure consistency)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.1%. Comparing base (426a1dd) to head (c3e150a).

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #1785     +/-   ##
=======================================
- Coverage   74.1%   74.1%   -0.1%     
=======================================
  Files        125     125             
  Lines      19481   19481             
=======================================
- Hits       14452   14449      -3     
- Misses      5029    5032      +3     

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