fixed phpdocs and incorrect exception names

lib/filestorage/file_archive.php

@@ -116,7 +116,7 @@ abstract class file_archive implements Iterator {
     /**
      * Tries to convert $localname into another encoding,
      * please note that it may fail really badly.
-     * @param strin $localname in utf-8 encoding
+     * @param string $localname in utf-8 encoding
      * @return string
      */
     protected function mangle_pathname($localname) {

lib/filestorage/file_storage.php

@@ -614,7 +614,7 @@ class file_storage {
 
         try {
             $newrecord->id = $DB->insert_record('files', $newrecord);
-        } catch (database_exception $e) {
+        } catch (dml_exception $e) {
             $newrecord->id = false;
         }
 
@@ -758,7 +758,7 @@ class file_storage {
 
         try {
             $newrecord->id = $DB->insert_record('files', $newrecord);
-        } catch (database_exception $e) {
+        } catch (dml_exception $e) {
             $newrecord->id = false;
         }
 
@@ -851,7 +851,7 @@ class file_storage {
 
         try {
             $newrecord->id = $DB->insert_record('files', $newrecord);
-        } catch (database_exception $e) {
+        } catch (dml_exception $e) {
             $newrecord->id = false;
         }
 

lib/filestorage/zip_archive.php

@@ -111,7 +111,7 @@ class zip_archive extends file_archive {
     /**
      * Returns file stream for reading of content
      * @param int $index of file
-     * @return stream or false if error
+     * @return resource or false if error
      */
     public function get_stream($index) {
         if (!isset($this->za)) {