Improved sys_fs module

- cellFsStat now accepts mounting points in the path argument.

- cellFsMkdir, cellFsRmdir, cellFsUnlink and cellFsRename are now using
the real path provided by the VFS.

- cellFsFtruncate, cellFsTruncate and cellFsFGetBlockSize are partially
implemented.

Note: I have spotted a bug in cellFsRename and cellFsRmdir (this has
nothing to do with the changes I made), but I don't dare to fix it since
I am not sure if I will break other functions with my solution.
Improved image decoding modules

* Huge improvement in the speed of cell{Png|Gif|Jpg}DecDecodeData when
reading input files.

Note: Sorry if this commit is too "small", but I need to sync every
change since I use two PCs.
Debugger improved: Instruction editor added

How to use the instruction editor:
1. Load an .ELF file
2. Select an instruction from any valid memory address inside any
thread.
3. Press 'E' key and have fun. :P

Note1: I suggest to remove the function InterpreterDisAsmFrame::DClick
and use InterpreterDisAsmFrame::InstrKey to do all debugging-related
actions (Add breakpoint, Edit, Step, Run, etc.) using the same keyboard
layout as debuggers like OllyDbg.

Note2: The final binary is 200 KB larger due to this feature. This issue
should be fixed in the future. This has probably something to do with
the #include's.
Debugger improved: Register editor added

How to use the register editor:
1. Load an .ELF file
2. Select any instruction from a thread. (This is a workaround to
activate the appropriate event listener. This will be changed in the
future).
3. Press 'R' key and modify any register you want.

Note:
The register editor only works with PPU and SPU threads.

Additional changes:
* Fixed the filesize problem caused by the instruction editor dialog.
* Instruction Editor: Fixed small issue in SPU threads
More SPU Instructions: Floating point arithmetic

Implemented Floating/Double-floating arithmetic operations: Add,
Substract and Multiply: FA, FS, FM, DFA, DFS, DFM respectively.

* Fixed issue in the register editor: Wrong value displayed when reading
64 bit or 128 bit registers.

* Fixed issue in the register editor: Error when writing to 128 bit
registers.
More SPU Instructions: Floating point comparison

* Implemented Floating/Double-floating comparison instructions:
FCGT, FCMGT, FCEQ, FCMEQ, DFCGT, DFCMGT, DFCEQ, DFCMEQ

* Implemented more Floating/Double-floating operations:
FMA, FMS, FNMS, DFMA, DFMS, DFNMS, DFNMA

* Implemented Double / Single floating-point conversion:
FESD, FRSD
Changed syntax of last SPU instructions
Merge pull request #5 from AlexAltea/master

Improved debugger, modules and the SPU interpreter