XH 1.5.10: Filebrowser: minor fixes/improvements

[cmb]

Hello Community,

for CMSimple_XH 1.6 some minor issues have been solved regarding the filebrowser:

1. r955: fixed PHP notices caused by Filebrowser ?
2. r1036: added Content-Type header to editorbrowser.php to force UTF-8
3. r1142: removed incorrect escape sequences in language strings

(1): That's happening when deleting a file, because the filebrowser sends a "file" parameter in this case, which sets $file what usually is meant for viewing or editing of a file (template, stylesheet, config, etc.) in the administration. AFAICS, there are no real issues besides the notice; however, it is easy to solve (only a small part of r955 has to be applied).

(3): There are two help strings with "...\'...", which are usually not seen, except when one requests the filebrowser language form via the URL directly, but it seems better to clean that up, anyway. Escaping single-quotes inside of double-quoted strings is invalid, and the backslash is kept.

I suggest we backport these fixes/improvements to XH 1.5.10.

Christoph