ecore-con: make curl support entirely runtime loaded via eina_module

this makes curl support a pure runtime-only thing. libcurl is loaded by
eina_module (dlopen/dlsym) when curl is actually first needed (when a
url connection/object is created). this means that ecore-con has no
link or compile dependencies on curl, only runtime, AND this saves
memory (due to curl inits using apparently a chunk of private pages).
so this saves memory and moves the dependency to runtime (though still
consider libcurl a dependency of efl - but like a binary executed,
it's at runtime).

ChangeLog

@@ -1,3 +1,8 @@
+2013-10-10  Carsten Haitzler (The Rasterman)
+
+        * Ecore-con: use dlopen/dlsym (eina_module) to load libcurl to
+        save memory (private pages) when not yet used by the process
+
 2013-10-10  Michael Bouchaud (yoz)
 
 	* Emotion: add two events to trigger webcam plug and unplug

NEWS

@@ -223,6 +223,7 @@ Improvements:
      - Add iterator for walking child of smart objects, table and a box.
     * Ecore_Con:
      - Rebase dns.c against upstream
+     - URL support now dynamically loads libcurl at runtime via eina_module.
     * Edje:
      - Entry: cursor position and location will be passed when it's really changed in case of mouse down, move, and up event.
      - Entry: remove ecore_imf_context_reset in mouse up event because it's useless.

configure.ac

@@ -1969,26 +1969,12 @@ EFL_LIB_END([Ecore])
 
 EFL_LIB_START([Ecore_Con])
 
-### Additional options to configure
-
-AC_ARG_ENABLE([curl],
-   [AC_HELP_STRING([--disable-curl], [disable curl support. @<:@default=enabled@:>@])],
-   [
-    if test "x${enableval}" = "xyes" ; then
-       want_curl="yes"
-    else
-       want_curl="no"
-    fi
-   ],
-   [want_curl="yes"])
-
 ### Default values
 
 want_ecore_con_local_sockets="yes"
 want_ecore_con_abstract_sockets="yes"
 
 if test "${have_wince}" = "yes"; then
-   want_curl="no"
    want_cares="no"
    want_ecore_con_local_sockets="no"
    want_ecore_con_abstract_sockets="no"
@@ -2027,8 +2013,6 @@ EFL_INTERNAL_DEPEND_PKG([ECORE_CON], [ecore])
 
 EFL_ADD_LIBS([ECORE_CON], [-lm])
 
-EFL_OPTIONAL_DEPEND_PKG([ECORE_CON], [${want_curl}], [CURL], [libcurl])
-
 EFL_OPTIONAL_DEPEND_PKG([ECORE_CON], [${want_cares}],
    [CARES], [libcares >= 1.6.1])
 AM_CONDITIONAL([HAVE_CARES], [test "x${have_cares}" = "xyes"])
@@ -2043,7 +2027,6 @@ fi
 
 EFL_OPTIONAL_DEPEND_PKG([ECORE_CON], [${want_systemd}], [SYSTEMD], [libsystemd-daemon])
 
-EFL_ADD_FEATURE([ECORE_CON], [curl])
 EFL_ADD_FEATURE([ECORE_CON], [cares])
 EFL_ADD_FEATURE([ECORE_CON], [local-sockets], [${want_ecore_con_local_sockets}])
 EFL_ADD_FEATURE([ECORE_CON], [abstract-sockets], [${want_ecore_con_abstract_sockets}])

src/lib/ecore_con/ecore_con_private.h

@@ -17,9 +17,6 @@
 #elif HAVE_OPENSSL
 # include <openssl/ssl.h>
 #endif
-#ifdef HAVE_CURL
-#include <curl/curl.h>
-#endif
 
 #define READBUFSIZ 65536
 
@@ -199,11 +196,10 @@ struct _Ecore_Con_Server
 #endif
 };
 
-#ifdef HAVE_CURL
 struct _Ecore_Con_Url
 {
    ECORE_MAGIC;
-   CURL *curl_easy;
+   void *curl_easy;
    struct curl_slist *headers;
    Eina_List *additional_headers;
    Eina_List *response_headers;
@@ -226,7 +222,6 @@ struct _Ecore_Con_Url
    Eina_Bool dead : 1;
    Eina_Bool multi : 1;
 };
-#endif
 
 struct _Ecore_Con_Info
 {