Update docs, v2.8.0

[timholy]

This updates the documentation (the main goal was to get precompile_blockers in, but other fixes were made too). A more thorough "cookbook" revision of the documentation may need to wait until later.

Also bumps version to 2.8.0.

[codecov]

Codecov Report

Merging #267 (c0014ea) into master (92094e2) will increase coverage by 0.29%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #267      +/-   ##
==========================================
+ Coverage   86.58%   86.87%   +0.29%     
==========================================
  Files          16       16              
  Lines        1878     2004     +126     
==========================================
+ Hits         1626     1741     +115     
- Misses        252      263      +11     

Impacted Files	Coverage Δ
src/invalidation_and_inference.jl	100.00% <ø> (ø)
SnoopCompileCore/src/snoopi_deep.jl	92.00% <0.00%> (-3.66%)	⬇️
src/parcel_snoopc.jl	78.15% <0.00%> (-0.23%)	⬇️
src/invalidations.jl	90.15% <0.00%> (-0.14%)	⬇️
src/visualizations.jl	0.00% <0.00%> (ø)
src/parcel_snoopi.jl	94.14% <0.00%> (+0.30%)	⬆️
src/parcel_snoopi_deep.jl	89.57% <0.00%> (+0.44%)	⬆️
src/parcel_snoopl.jl	90.00% <0.00%> (+0.52%)	⬆️
src/write.jl	92.30% <0.00%> (+1.00%)	⬆️
... and 1 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 92094e2...c0014ea. Read the comment docs.