Remove unnecessary version pins from requirements.pip.
Remove unnecessary version pins from requirements.pip.

TouK/vumi,vishwaprakashmishra/xmatrix,harrissoerja/vumi,harrissoerja/vumi,vishwaprakashmishra/xmatrix,harrissoerja/vumi,vishwaprakashmishra/xmatrix,TouK/vumi,TouK/vumi