Make search match with plural, possessive, etc. forms

[jonolds]

Is your feature request related to a problem? Please describe.

When I want to read about Matt Mullenweg's latest shenanigans, I search for "mullenweg", but it masses posts like "WPE's response to Mullenweg's motion to dismiss is out."

Describe the solution you'd like

include posts like the one in the example above.

Describe alternatives you've considered

an overly-complicated query