cs_prefs.cpp

    This fixes a bug that can cause debts to NEVER get updated.
- client: added "abort_jobs_on_exit" feature
    (available by --abort_jobs_on_exit cmdline
    or <abort_jobs_on_exit> in cc_config.xml).
    If set, when the client is exited by user request
    (this includes signals on Unix)
    it marks all pending jobs as aborted,
    and does a scheduler RPC to all projects with jobs.
    When these are completed the client exits.
    This is useful when BOINC is being used on grids
    where it is wiped clean after each run.

svn path=/trunk/boinc/; revision=17300