Initial code for new grid-type boinc. #3540

Gridmanager and condor_submit now recognize new grid-type 'boinc'.
The gridmanager has new classes BoincJob and BoincResource, and
understands new boinc gahp commands. Large chunks of this code remains
to be written.
Additional code for new grid-type boinc. #3540

All gahp command handlers implemented.
Major pieces remaining:
* Coordinating batch submission.
* Lease renewal.
* Failure recovery.
More work on new grid-type boinc. #3540

* BoincAuthenticator attribute
* Support talking to multiple Boinc servers
* Updates of gahp protocol
* Add batch-management code, including submission and lease renewal
Correct some boinc gahp command names. #3540
Merge branch 'V7_9-gt3385_boinc-branch' into master-gt3385_boinc-branch
Fix some bugs in gridmanager boinc code. #3540
Merge branch 'master' into master-gt3385_boinc-branch
More changes in the gridmanager boinc code. #3540
Better failure handling for boinc jobs during submission. #3540

If we restart during submission and and boinc server is down, don't stay
stuck waiting to find out if the submission succeeded.
Retry boinc batch query on "no batch named" error. #3540

The query is retried without the offending batch.
Fix boinc lease management and other timer values. #3540
Remove unnecessary code and data in BoincJob. #3540
Issue Boinc retire batch command when last job is done. #3540
Merge branch 'master' into master-gt3385_boinc-branch
Update BoincResource timer values after merge from master.
Store boinc authenticator in its on own file, not in the job ad. #3540

This allows the user to keep the authenticator secret.
Don't use 'stderr' as a name. #3540
Add Boinc GAHP external. #3540

The Boinc GAHP is currently kept in the BOINC git repository. Add it as
an external in the HTCondor build.
Allow canceling of jobs with BOINC ERROR status. #3540
Update BOINC_QUERY_BATCHES gahp command syntax. #3540

The updated command takes a time of last query and returns the time of
the current query. This allows us to ask for only jobs that have changed
status since the last time we asked.
For now, we just ask for all changes since the beginning of time (the
old behavior).