Changes include patches to
 * Handle gcc 4.4.1's foibles.
 * Instrument {{{toku_os_pread}}}
 * Release the lock during I/Os for queries (#3039)
 * Simplification of the ydb lock (no more backoff)
 * Use {{{DB_TXN_NOSYNC}} for several tests (which speeds them up).
 * Set the redzone to zero for several tests  (so they can run on machines with little free space). (#3111)
 * Add  helgrind and valgrind suppressions to some tests.
 * Add dollar-id-dollar to several files.
 * Declare the schedule status values to be volatile.
 * Add a method to the toku {{{RWLOCK}}} to effectively grab the read lock and then release it quickly.  (With only one condition variable acquisition.)
Fixes #3039. close[t:3039]
Refs #3111,   #3112,   #3119,   #3125,   #3126,   #3128,   #3131,   #3133,   #3142,   #3152.
   [t:3111] [t:3112] [t:3119] [t:3125] [t:3126] [t:3128] [t:3131] [t:3133] [t:3142] [t:3152].


git-svn-id: file:///svn/toku/tokudb@26785 c7de825b-a66e-492c-adef-691d508d4ae1