Fix VS 2012 build (unsupported nearbyinf, truncf)
Remove compiler specific preprocessor directives
Vectorize game_of_life with pnacl

Required converting an int8 -> int32 cast to scalar code
Merge pull request #540 from halide/linear_solver

Added a linear solver mutator.
Added LinearSolve.h/cpp to CMake build.
Add EXPORT qualifiers
Added comments to the new versions of expr_uses_var(s). Added EXPORT macros to expr_uses_var for Windows support.
Merge pull request #545 from halide/scoped_expr_uses_vars

Added an optional scope argument to expr_uses_var(s).
Fix store collector for upsample pattern

The store collector was bailing out when it found too many stores,
rather than only considering the first few. e.g:

f[ramp(a, 2, 4)] = ...
f[ramp(a+1, 2, 4)] = ...
f[ramp(b, 2, 4)] = ...
f[ramp(b+1, 2, 4)] = ...

can be rewritten into two interleaving stores, but the store collector
was finding four stores and bailing entirely.
Merge pull request #534 from pgec/VS2012_build_fix

Fix VS 2012 build
Add some braces.
Merge branch 'master' of github.com:halide/Halide
Merge master