Minor spelling and wording changes

[gammazero]

This is an accumulation of minor spelling and wording changes.

Closes #766

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.40%. Comparing base (3a844a9) to head (2ef7463).
Report is 4 commits behind head on main.

@@           Coverage Diff           @@
##             main     #768   +/-   ##
=======================================
  Coverage   60.40%   60.40%           
=======================================
  Files         245      245           
  Lines       31126    31126           
=======================================
+ Hits        18801    18802    +1     
- Misses      10645    10647    +2     
+ Partials     1680     1677    -3     

Files with missing lines	Coverage Δ
bitswap/server/internal/decision/scoreledger.go	94.11% <ø> (ø)
mfs/dir.go	53.79% <ø> (ø)

... and 11 files with indirect coverage changes