Added markdown for the header diffs
Fixed some stuff
Fixed some stuff
Revert "Fixed some stuff"

This reverts commit 8491e3a7101a14303fce9de4a80a6b2fa90d1d23.
Implemented word-based diffs of headers
Fix bug, modifiedness scoring
Fix flake issue and broken js test.
Merge pull request #159 from MandMk/diffed-header

Added javascript for the header diffs