Ignore files copied into hphp/runtime/ext_zend_compat/newrelic
from newrelic source.  The ext_zend_compat directory is needed
to build static extensions.
Remove rrh speculative phpDebuggerAnyErrorHook which was added
to support NewRelic style profiling, but proved to be too inefficient.
Back out changes to support onFunctionPreReturn and its ilk.
The easiest way to do this is to incref/decref in the newrelic extensions.