Support templates

[Dieterbe]

includes previous PR's (cache and statsd objects), but this is cherrypickable.

[yml]

Blind guess since I have not looked at the code in details but the error in travis seems to comes from the fact that ConfigParser has been renamed in python 3.

Something like this might help:

try:
    import configparser
except:
    from six.moves import configparser

[Dieterbe]

actually i believe importing configparser in py3 should work, in py2 it's ConfigParser.
do we need an external module like six?

[brutasse]

configparser doesn't have the same API in python2 and python3 so it's not as simple as changing ConfigParser to configparser. I'd rather have templates configuration directly in a templates section in the main yaml file… It's annoying not to have it with the same syntax as graphite-web but it's also annoying to have 2 config files in different formats.

[Dieterbe]

ok so this PR is no good then