Using --https option fails when creating the reference repository.

[ktf]

Tai has a problem on his mac:

$ git cms-addpkg RecoMET/METProducers
No release tags specified, using default CMSSW_7_0_0_pre0.
You are on branch CMSSW_7_0_X
Checking out RecoMET/METProducers in tag CMSSW_7_0_0_pre0.
Your reference git repository does not seem to exist, would you like
to create it? [ y / N / ? ] yCloning into bare repository
'/Users/sakuma/.cmsgit-cache'...
fatal: unable to access 'https://github.com/cms-sw/cmssw.git/': SSL
certificate problem: unable to get local issuer certificate

the --https option would probably solve this issue, however it's apparently not working correctly.