Installing lxml

It turned out to be hugely difficult to install lxml on my Ubuntu lts 14.04 virtual instance.

I think there were several problems.  But the really tough one was pointed out here:

http://stackoverflow.com/questions/16149613/installing-lxml-with-pip-in-virtualenv-ubuntu-12-10-error-command-gcc-failed

Basically, I needed more memory.  So I enlarged the RAM for my digital ocean droplet. 

(I found nice instructions for doing this here.  I don't think I would have had the courage to destroy my own droplet without someone saying that they had done it.  Even so, it was difficult.)

And the error changed from gcc error status 4 to gcc error status 1.  It reported failing to find -lz.

So I added the libz-dev package and ran the following:

sudo python2.7 setup.py clean build --with-cython install

from a git clone of the lxml directory.  So the good news is that now it's installed with cython so maybe it will be faster than it otherwise would have been.