Properly fixate Mercurial version to only be for Python 2.7 to work around Travis-Python 3-Mercurial issue.
Properly fixate Mercurial version to only be for Python 2.7 to work around Travis-Python 3-Mercurial issue.

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