THRIFT-926. cpp: Thrift: throw bad_alloc when malloc fails, not something else

THRIFT-926. cpp: Thrift: throw bad_alloc when malloc fails, not something else

When malloc/realloc fail, we've typically just thrown a TException. This
allows a server that should simply crash when out of memory to survive
in a strage state, with various bad consequences. Instead, we should
throw bad_alloc and just not catch it (or if we decide to, be very
careful to respond properly).

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@1005167 13f79535-47bb-0310-9956-ffa450edef68