branching off 0.11 for work on stampede protection
more work on stampede protection, refs #668
added stub abortedCacheCreationCallback and adjusted callback signatures, refs #668
merge 56c5f2fa0d315b70403aeea4872a9af967c324e7
merge ef8ab573c28ca35bb58d82455290fce10fb29080 to 577c7ea51495cc54eaf7fbe32e713ef16e61702a (from 0.11)
merge 3dc9c13b2a6ed1886c339c18aba558ac1d5a3a6e to 80deaff543fa0162c0dd5201810c680dd5c66d71 (from 0.11)
merge 069c0388ff507c56666fbeb64a57457ca39259b3 to 74bd27722490c5592b15b4a889e52d3eb9170735 (from 0.11)
merge 09cef394106bb615c27f9bed34cbd9b9c9f811e3 to 1c759752869500fd6bdb6abe1ef07be46b632c9a (from 0.11)
merge [2601:3543/branches/0.11]
porting branch to 1.0
set lock only if action is cacheable
release stampede lock on view when execution needs to start over in case action is cached, but view isn't
merge 7981e967ad7879878478a433ceeb047d527fca7f to f35756abca0bc084a90d822be542cbd7bab89bfe (from 1.0)
dox
hand action groups, not view groups (they don't even exist) to aborted... callback if output type is not cacheable
Merged support for anti-stampede callbacks in Execution Filter (from 1afe3b3fb50aaaa183ec7484468ac1e0c7a12e62 to a3429744ff1233130431c6286c79a4b0d5b1b343 (from david-stampede_protection)). Example implementation to follow. Closes #668