Add custom highlight support

[daniellandau]

Although #1101 has similar goals, the implementation is different.

[daniellandau]

Um, the Travis build seems to fail on something Bloodhound related, and I didn't touch anything there.

[daniellandau]

It would be nice to get some feedback on whether the underlying idea here is fundamentally within this projects scope. Updating my PR for changes in master took a non-negligible amount of work, and if there is no chance to get this merged, I will save the trouble of doing it again. ping @jharding

[bronson]

I'd suggest squashing the two commits into one. Other than that, this PR looks good.

I sure need this functionality. Wish @jharding would take a look at it or call for help.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
0 out of 2 committers have signed the CLA.

❌ Daniel Landau
❌ daniellandau

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[bronson]

Project has been dead for 4 years but make sure to sign the CLA!