Change terminology in log from "remerge" to "recheck"
Change terminology in log from "remerge" to "recheck"

Summary:
It used to be that the set of files to merge and the set of files to check were the same, but that changed in D17821995.

Since we're printing the set of files to check, let's make the terminology more accurate here.

Reviewed By: gabelevi

Differential Revision: D18275370

fbshipit-source-id: c2d98d26c9dcb89a98efdd8ba641f7bbf2036c6f

mroch/flow,samwgoldman/flow,mroch/flow,samwgoldman/flow,facebook/flow,facebook/flow,facebook/flow,samwgoldman/flow,facebook/flow,mroch/flow,facebook/flow,samwgoldman/flow,mroch/flow,facebook/flow,samwgoldman/flow,samwgoldman/flow,mroch/flow,mroch/flow,facebook/flow,samwgoldman/flow,mroch/flow