use macro for EXTERN "C" begin and end lines in header files to clean up the headers, and to eliminate a format bug in emacs.

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@1291 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/include/switch_apr.h

@@ -39,12 +39,7 @@
 #ifndef SWITCH_APR_H
 #define SWITCH_APR_H
 
-#ifdef __cplusplus
-extern "C" {
-#ifdef __FORMATBUG
-}
-#endif
-#endif
+BEGIN_EXTERN_C
 
 #include <apr.h>
 #include <apr_network_io.h>
@@ -1435,8 +1430,6 @@ SWITCH_DECLARE(switch_status) switch_mutex_init(switch_mutex_t **lock,
 /** @} */
 /** @} */
 
-#ifdef __cplusplus
-}
-#endif
+END_EXTERN_C
 
 #endif