RSX Debugger, Mem. Viewer and module improvements

* Small cleanup in cellJpgDec and cellPngDec.
* cellPamf added to the project and a few test lines added to
cellPamfGetHeaderSize(2).
* Improved speed of the Raw Image Preview on the the Memory Viewer.
* Now you can click on the shown buffers / textures in the RSX Debugger
in order to see them in full size. More settings added to the tabs.
* Fixed cellFsStat in order to fix the crash aused by opening
directiories. The solution is really *really* ugly. Once vfsDir is
ready, I will replace it with something better.