Support sorting files using mtime or size
Support sorting files using mtime or size

This introduces Apache-style URL arguments to specify how to sort the
entries in the generated listings:

 - Appending "?C=M" sorts by modification time (mtime).
 - Appending "?C=S" sorts by file size.
 - Any other (or no arguments) use the default sorting, by name.

janglapuk/ngx-fancyindex,cinderblock/ngx-fancyindex,cinderblock/ngx-fancyindex,janglapuk/ngx-fancyindex