Include <arpa/inet.h> when checking for htonll

Otherwise we clobber htonll in OS X Yosemite

Change-Id: Ica6b24e6752e7f4d68974ea613d460d8b94bacea
Durability timer fixes..

Change-Id: I1d0a9138f1018b1408fc8e89b452fbbbcbe0dbc5