As reported by Rainer Jung, Curl may not be mandatory to build
ModSecurity core. This patch make it optional by:
- Concentrate all downloads using curl on msc_remote_rules.c
- Split Curl build definitions checks into: WITH_CURL, WITH_REMOTE_RULES
and WITH_CRYPTO.
- WITH_CURL: Contains Culr headers and binaries during the build time.
- WITH_REMOTE_RULES: Currently enabled if Curl is present.
- WITH_CRYPTO: Set if apr tool was compiled with crypto support.
- Renames msc_remote_grab_content to msc_remote_download_content
Originally the SecRemoteRules fetch the rules from an remote server in an
specific format, using cryptography. This patch adds the possibility to
load rules in plain/text format.
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.
