print better error message

print better error message

Summary:
before:

E0203 12:32:34.548096 3354863 [admonitor-local] Singleton.cpp:72] Singleton of type N8facebook12configerator22ConfigeratorStaticDataE has a living reference at destroyInstances time; beware! Raw pointer is 0x7fd6ccc81000. It is very likely that some other singleton is holding a shared_ptr to it. Make dependencies between these singletons are properly defined.

after:

E0203 13:48:09.013022 3913115 Singleton.cpp:72] Singleton of type facebook::configerator::ConfigeratorStaticData has a living reference at destroyInstances time; beware! Raw pointer is 0x7f6f7dc4c000. It is very likely that some other singleton is holding a shared_ptr to it. Make dependencies between these singletons are properly defined.

Test Plan: run it

Reviewed By: chip@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1822466

Signature: t1:1822466:1423000686:345f40fa706701476256a7157468521bc69166a0