Updated modules to allow for partial overrides without errors

Only define functions if they have not been defined before, e.g. in themes. This makes it possible to override parts of a module and still use the other functions.

mod/api.php

@@ -1,10 +1,8 @@
 <?php
-
 require_once('include/api.php');
 
+if(! function_exists('oauth_get_client')) {
 function oauth_get_client($request){
-
-
 	$params = $request->get_parameters();
 	$token = $params['oauth_token'];
 
@@ -19,9 +17,10 @@ function oauth_get_client($request){
 
 	return $r[0];
 }
+}
 
+if(! function_exists('api_post')) {
 function api_post(&$a) {
-
 	if(! local_user()) {
 		notice( t('Permission denied.') . EOL);
 		return;
@@ -31,9 +30,10 @@ function api_post(&$a) {
 		notice( t('Permission denied.') . EOL);
 		return;
 	}
-
+}
 }
 
+if(! function_exists('api_content')) {
 function api_content(&$a) {
 	if ($a->cmd=='api/oauth/authorize'){
 		/*
@@ -114,3 +114,4 @@ function api_content(&$a) {
 	echo api_call($a);
 	killme();
 }
+}