SERVER-16041 cache_size estimation does not work on OSX
Import wiredtiger-wiredtiger-2.4.0-275-gc4f14ea.tar.gz from wiredtiger branch develop
Tune WT default cache_size up to 50% memory
SERVER-16023: abort mongod on WT_PANIC
update-vendor-wiredtiger: exclude tools/third_party
Import wiredtiger-wiredtiger-2.4.0-285-g0d497d3.tar.gz from wiredtiger branch develop
fix compilation for WT Windows