handle 'e' set a resize handle at east side, 'w' at west side.

The height handling code was triggered before the width handling code
and thus the right pane was below the other panes during the height
calculations which caused strange effects. Now the height handling code
is called again after adjusting the width of the right pane.

This adds more tolerance to the width calculations of the media manager
panes which avoids that the right pane is displayed below the other
panes.

fixed resizing mediamanager panels in Chrome using browser sniffing (FS#2351) - any better solution welcome

fix widths of panels in fullscreen mediamanager to be 100% when resizing (FS#2351) -- please test in different screen sizes, etc

Now params_toarray() correctly decodes parameters on parsing query
strings

This reverts commit ba6c070e.
This reverts commit 92351008.