Implementing satus mapping and severity mapping based on [1] [2] [3] [4]

[1] https://www.mediawiki.org/wiki/Bug_management/Bug_report_life_cycle
[2] http://www.bugzilla.org/docs/3.6/en/html/api/Bugzilla/WebService/Bug.html
[3] https://sourceforge.net/rest/p/pywikipediabot/feature-requests/347/
[4] https://sourceforge.net/rest/p/pywikipediabot/bugs/1669/

Change-Id: I4d51c2f3219484db0e090f8484b89d2e65f3fdcd