[ticket/9556] Drop php closing tags, add trailing newline

Closing tags converted using Oleg's script.
remove-php-end-tags.py -a .

Trailing newlines added using the following where $ext is file extension.
find . -type f -name "*.$ext" -print | xargs printf "e %s\nw\n" | ed -s;

Extensions: php, css, html, js, xml.

PHPBB3-9556

phpBB/includes/diff/diff.php

@@ -1144,5 +1144,3 @@ class diff3_block_builder
 		array_splice($array, sizeof($array), 0, $lines);
 	}
 }
-
-?>

phpBB/includes/diff/engine.php

@@ -550,5 +550,3 @@ class diff_engine
 		}
 	}
 }
-
-?>

phpBB/includes/diff/renderer.php

@@ -856,5 +856,3 @@ class diff_renderer_side_by_side extends diff_renderer
 	}
 
 }
-
-?>