Add link to subcompaction wiki.
fix typo and changed the wording little bit to help explaining the example
Revert “Fix a typo in number of sorted run” (not a typo)
Updated Universal Compaction (markdown)
Fix a typo in number of sorted run
add parentheses for calculating size_ratio_trigger
use consistent description for options only for level-based compaction.
It should be R4 here.