Openbazaar python launcher

new pull request after 1st round of reviews.
Thanks @Renelvon this has the merged changes from your repo.

(@Renelvon I kept that REVERT commit you put there as I'm not sure I understood what was right or wrong about it, I figured it'd be easier to fix here now)
I know, but there is reason for that, supposedly. It seems there is special trouble installing `pysqlcipher` on Mac, and that's why you have to install it last.

I won't press it anymore, since I can't test it (I 'm on Linux Mint 17). I am just saying we shouldn't revert changes during a merge from master. The proper way to revert #612 is to execute
```
git revert 77b0dab
```
so that the change is documented. @dionyziz can help you with that.