Load studies from Report class during init.
create_report for all standard studies executed in report_tool.

Conflicts:
	vizGrimoireJS/report_tool.py
ContributorsNewGone and QuartersData studies now executed from generic code in report_tool.py.

Conflicts:
	vizgrimoire/analysis/contributors_new_gone.py
	vizgrimoire/analysis/quarters_data.py
Added real author of this code.

Conflicts:
	vizgrimoire/analysis/times_tickets.py
Include studies metrics in all data sources.

Conflicts:
	vizgrimoire/SCR.py
Added grimoirelib_alq to PYTHONPATH for ages study.
Removed specific code for building just studies.
Added new participants metric to qaforums.
Added participants metrics to qaforums.