Clarify hgrange and its arguments. Should now be less confusing when firstBad is a merge.
Clarify hgrange and its arguments. Should now be less confusing when firstBad is a merge.

nth10sd/funfuzz,nth10sd/funfuzz,MozillaSecurity/funfuzz,MozillaSecurity/funfuzz,MozillaSecurity/funfuzz,nth10sd/funfuzz