Adds SecRemoteRules as an build option

SecRemoteRules adds a new dependency to libcurl. Before only mlogc was
depending on libcurl. SecRemoteRules also depends on the apr-tools with
crypto support, which (as reported by our buildbots) is not default in
some environments such as: MacOS X. This commit disable SecRemoteRules
support if apr-tools was not compiled with crypto support.