See http://boinc.berkeley.edu/trac/wiki/PerAppCredit
If enabled (by the <credit_by_app> config flag)
validators will maintain on a per-(app, user, credit type) basis,
and same for teams,
in new DB tables credit_user and credit_team.
This info is displayed in the web site, on user and team pages,
using project-supplied functions to generate the HTML.
Note: update_stats doesn't decay the recent-average values
for per-app credit; I'll add this if needed.
I set out to make project-specific prefs use the same object framework
(PREF_BOOL, PREF_NUM etc.) as other prefs.
This turned out to be infeasible, so I settled for a code cleanup instead.
The reason it's infeasible is that the "other prefs" code
uses a SAX parser (xml_parser_create() etc.),
while the code for project-specific prefs uses the primitive
parse_element() and parse_next_element() functions in util_basic.inc.
If I'm going to change anything, I want to switch to a DOM parser
(e.g. simplexml) for both purposes.