Add parse data function to allow parse log lines from data stream
Merge pull request #3 from bogdangi/parse_data

Parse data
New filter: backend

Filters log lines by the HAProxy backend the connection was handled
with.
Fix HTTP request regular expression

If a request path was for the front page (i.e. "/") the regular
expression would fail to parse it.

This commit fixes the regular expression and adds a test for it.