Add Dockerfile for running inside a docker container

(see http://docker.io)
urllib2 replaced by requests

doc: http://docs.python-requests.org/en/latest/
urllib2 replaced by requests
Update README.md
Merge pull request #16 from djmaze/patch-1

Add Dockerfile for running inside a docker container
add htag directory creation
daemon script for debian

by PoGo606 - https://github.com/PoGo606/twitter-rss/commit/b44b0f6b0c8630fa83b46148702f05b55664935b
Merge branch 'daemon'
added daemon procedure
screenshots added
caching feed feature now working
more information about install/config
change web server to gunicorn

* run.py doesn't launch the webserver in subprocess anymore
* gunicorn is now used as webserver
* supervisor is used to ... supervise all the process
* added supervisord.conf
* README updated to reflect changes
added update script in supervisord.conf

+ update script now updated to work with new user.txt and htag.txt
method to change port updated to match gunicorn use
supervisor description modified
server url not hardcoded anymore
default port for twitter-rss will stay 5000
support user/htag alone in user.txt/htag.txt
regex rewrited