Start giving support to duplicates and fixed version

WIP though
More deps found
Dummy implementation to get_id_url

+ Fixes on SQLite backend
Added --upload option to the crash digger

* It must exist the Duplicate database to do the checking for duplicates
Added script to set Package field to invalid crash reports
More deps
Give support to retrace gzip files
Upload the sqlite crashdb backend configuration
Use real type for sym_stacktrace
Store stacktrace as a BLOB

With regards to a problem found in a struct with int[] elements, the print
from gdb is not a correct string so we store it verbatim
Fix regression uploading a crash report not gzipped
Added documentation for retracing a single crash
Add old repository to get packages from there
Set manually the dependencies and package when the crash misses that info
Start implementation sqlite backend with crash_url

Instead of storing the crash BLOB in the DB
Implement crashes_base_url to set the URL for a report

Unit tested
Implement simple HTTP file upload

For python2 and 3 without external libraries
Fix minor bug when crashes_base_url is using a custom port
Added missing dependencies for 3.2

Due to a bug in crash-set-package-field.py script
Added support to get_unfixed to sqlite crashdb backend