Initial prototype for an easier way to impose boundary conditions in Halide.
Fix C++11 arbitrary number of arguments support.
Move functionality to BoundaryConditions namespace.

Add a paltry smattering of comments barely sufficient to start
feedback process.
Merge branch 'master' into boundary_conditions

Conflicts:
	Makefile
Add some explanatory comments relating mechanism to GL texture wrapping modes.
Merge pull request #361 from steven-johnson/master

Make AArch64 the default for 64-bit ARM
Merge branch 'master' into boundary_conditions
Added some comments to explain acquire/release.
Changed to passing Exprs by value in stead of const reference to be
consistent with style elsewhere.

Added const qualifier to Var's cast to Expr operator per a report of
compiler errors from Takayuki Muranushi. It seems like the correct
thing and that it was missing was an oversight, but perhaps I'm
missing something.
Silence linkage warnings for 64-bit targets
Add support for applying boundary conditions to ImageParam, Image<T>,
and similar types.

Add support for automatically applying boundary conditions at the
bounds of ImageParam, Image<T>, and similar types.

Add std::vector<Expr> and std::vector<Var> overloads for operator() in
Image<T> and ImageParam types.
Fix boundary conditions applied to ImageParam and Image<T> to use
implicit variable names (_0, _1, _2, etc...)
Merge pull request #357 from halide/boundary_conditions

Boundary conditions