macros for turning off bounds checks. fixes #1392

`@inbounds expr` allows bounds checks to be omitted for code syntactically
inside the argument expression.

adds @inbounds to matmul, comprehensions, and vectorized binary operators.
Merge branch 'master' of github.com:JuliaLang/julia into jb/inbounds
Merge branch 'master' of github.com:JuliaLang/julia into jb/inbounds
clarify boundscheck expressions
Merge branch 'master' of github.com:JuliaLang/julia into jb/inbounds
Merge branch 'master' of github.com:JuliaLang/julia into jb/inbounds

Conflicts:
	src/alloc.c
	src/codegen.cpp
	src/jltypes.c
Reorganize sparse matrix code into a module.
export only a well-defined interface, while hiding internal functions.
Create a sparse/ directory for all the sparse matrix code.
Rename the cscdiagit type to SpDiagIter
Fix boolean setindex!
Add convert(SparseMatrixCSC{Tv,Ti}, M::Matrix)
pkg2: not all versions of `git branch` support the `-q` option.
Changes to contrib/repackage_system_suitesparse4.make to more closely match how SuiteSparse is built in deps/
Gets rid of conflicting symbols warnings on Homebrew, and also saves a bit of disk space, as libraries are now dynamically linked instead of statically linked
Merge pull request #3507 from staticfloat/homebrew

Changes to contrib/repackage_system_suitesparse4.make
WINDOWS: fix 78cc53082aa5632d0835518663f940301b0116e5
Fix paths in test/readdlm.jl
Merge pull request #3508 from staticfloat/fixpaths

Fix paths in test/readdlm.jl
Add in option for JULIA_PKGDIR when packaging mac app
Merge pull request #3510 from staticfloat/pathfix

Add in option for JULIA_PKGDIR when packaging mac app
Fix #3509
More arpack tests. Fix ARPACKException. Fix float32 case.
Merge branch 'master' of github.com:JuliaLang/julia
Updated doc for keys(d::Dict) and values(d::Dict) to reflect that they return an Iterator.
Fix #3511.
Enable complex tests for ARPACK.