Numerous updates

[greglandrum]

Some of the changes here:

• Use rdkit master instead of a particular release. We should be sure to change this before merging to master
• Switch the linux and mac builds to boost 1.63
• Pin the conda version in an attempt to avoid their new builds

I've tested the full thing on the Mac and on CentOS6 with py36 (py35 seems to always be the same) and py27.
Most of this has also been tested on windows, but I will confirm that again.

I have not updated the other pieces, the cartridge build in particular, but that should also be done.

[rvianello]

the changes look good to me, I'll send you a message about the cartridge recipes, partly related to the status of the other pending PR.

[rvianello]

this 'make install' in the osx branch looks a bit odd to me, I guess there's probably a reason for introducing it, but I'll comment anyway, just in case it's an oversight.

[greglandrum]

I put that in there when I was in the flailing "why the hell doesn't this work?" stage caused by the new conda python builds.
I'll try taking it out to see if things still work without it.

[greglandrum]

@rvianello : I think this is now mergeable as is.
I've tested the rdkit-postgresql95 recipe on the mac and it looks fine. Do we still need to support building older versions?

Once this is merged onto development, I think we should consider pushing it to master as well.

[rvianello]

@greglandrum thanks for the updates, and sorry for the slow feedback. the rdkit-postgresql95 recipe worked fine with the upstream 'postgresql' in my tests too, and I also agree that there should be little need for building the cartridge for the older versions (once the master is updated we could maybe consider removing some of these recipes that are no longer useful).