Removed PCRE dependency when linking to libutils

cf-upgrade refused to link to libutils without -lcrypto and -lpcre. The
PCRE dependency has been removed in this patch, OpenSSL dependency is
still TODO though.
Remove mandatory OpenSSL dependency from libutils.
LOUDLY mention that platform.h needs to come first.
Don't emit deprecated warning for the snprintf vs system sprintf test.
Merge pull request #1851 from jimis/cfupgrade

Remove dependencies from libutils.