pybabel failing to update in osmocom vm

[kheimerl]

Seems to be this issue: python-babel/babel#91

[kheimerl]

the change from 'w' to 'wb' is a work around, but there's no pip release for this that works at the moment.

[i-am-nut]

I faced many issues while installing pip dependencies with Python3 on osmocom vm. So i went throught using Python2.
Could you setup osmocom vm successfully with Python3? @kheimerl

[kheimerl]

I was able to get it set up. It wasn't too bad with the above workaround.