kes Move the checking of the database in initializion of the Director

kes  Move the checking of the database in initializion of the Director
     to after we drop privileges.  This avoids the need for both root
     and bacula access to the DB.
kes  Correct a misplaced variable definition in src/filed/backup.c
kes  Correct how the new batch insert db_create_attributes_record()
     uses the arguments.  Caused a seg fault in bscan.
kes  Implement lock() and unlock() methods in DEVICE class.
     Implement block() and set_block(xx) methods in DEVICE class.
kes  Modify bnet_connect() so that it uses time() to check for the
     wait time expiring (on some OSes, some system calls may not
     return immediately).
kes  Modify Verify to obtain the previous JobId when it is actually
     running rather than at schedule time (as it was in 1.38.x).
kes  Fix src/job.c to handle MaxWaitTime correctly.  This should
     fix bug #802.
kes  When checking pid in pid file, continue running if the pid is
     the same as ours. This occurs on IRIX after a system crash.
     Fixes bug #797.