* asciidoc indirectly requires docbook-style-xsl on el6 and f20,
but not on el5. Resolve failure to build tito with tito on el5:
"I/O error : Attempt to load network entity"
* Resolve "egg missing file" on el5 due to busted symlinks
from 20c4f1b7c0.
* Add functional test to build tito with itself in order to
catch problems like the ones above.
Closes https://github.com/dgoodwin/tito/issues/133
Add URL of upstream tito repo to HACKING, then
symlink HACKING as README.md in each Dockerfile dir.
Why?
If a README.md exists in same dir as Dockerfile (incl. symlink),
and it's set up as a
[trusted build](https://index.docker.io/help/docs/#trustedbuilds),
then index.docker.io automatically shows the readme on the info
page of the trusted build.
