PolarSSL: update to current stable version (1.3.4)

I just removed Externals/polarssl/, added the new version, then deleted
the following files/directories:

DartConfiguration.tcl
Makefile
doxygen/
library/Makefile
programs/
scripts/
tests/
visualc/
PolarSSL: adapt Dolphin to new version

- strip down PolarSSL's CMakeLists.txt
- switch to the PolarSSL 1.3 API
- use entropy interface instead of havege (PolarSSL 1.3 has disabled
  havege by default because it is "considered unsafe for primary usage")
- add VS2013 .vcxproj file
PolarSSL/CMake: validate cached values
CMake: check PolarSSL version
Merge pull request #102 from Tilka/polarssl1.3

Update PolarSSL to current stable version
ogl: optimize real xfb a bit

Both nvidia + mesa seems not to optimize x / (2**n) to x >> n, so we do it ourself.
merge common parts of encoding shaders
MathUtil: Change Log2 return value to int

Log2(u64) can't be bigger than 63, so there is no need in forcing a 64 bit value.
So just using a common int seems more natural.
TextureConverter: Use Log2() and shifts instead of multiplications/divisions
Rewrite texture tiling implementation

inline halfxb

So we know which is the first pixel by masking.

inline xl

inline xb a bit

inline yl

inline uv1.x shift

remove likely wrong guessed ternary operator

add pixel layout comment

inline xel

optimize the shifts a bit

inline xb

optimize shifts in a second step

extract xb

rename all variables

calculate cache line by position.x

Revert 5115b459f40d53044cd7a858f52e6e876e1211b4 "optimize the shifts a bit"

It seems I was wrong, the other way is the more natural.

use x_virtual_position instead of uv1.x for x_offset_in_block

This looks more natural and the offset should be masked anyway.

substitude factor with cache_lines

move 32bit logic in a conditional block
calculate constant values on shader compilation
Merge duplicate parts of sampler into header
remove (ATTR|VARY)(IN|OUT) macros