Disable 'branch' field except for new mapping

Since the branch's name is used as key to identify the mapping, it is
not possible to change it. To avoid confusing behavior, the input field
is disabled, except for the new mapping row.

Fixes #243

Author: dregad

Source/pages/repo_manage_page.php

@@ -194,7 +194,11 @@ function convert_to_key_value( $p_array ) {
 
 	foreach( $t_mappings as $t_mapping ) {
 		$t_branch = str_replace( '.', '_', $t_mapping->branch );
+		# Since it is not possible to update the branch's name (see #230),
+		# the input field is disabled, except for the 'new mapping' row
+		$t_disabled = 'disabled';
 		if( is_null( $t_mapping->branch ) ) {
+			$t_disabled = '';
 ?>
 			<tr class="spacer"></tr><tr></tr>
 <?php
@@ -204,7 +208,9 @@ function convert_to_key_value( $p_array ) {
 				<td class="center">
 					<input type="text" name="<?php echo $t_branch ?>_branch" value="<?php
 						echo string_attribute( $t_mapping->branch )
-						?>" class="input-sm" />
+						?>" class="input-sm"
+						<?php echo $t_disabled; ?>
+					/>
 				</td>
 				<td class="center">
 					<select class="input-sm" name="<?php echo $t_branch ?>_type"><?php