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
Pkg2: slight error/info messaging tweak.
give a chance to set USE_BLAS64 in Make.usr
handle missing newline after last row
use system libopenblas via set USE_SYSTEM_OPENBLAS=1
Add fieldoffsets(DataType)
fix #3619, segfault in resize!
Merge pull request #3617 from simonster/fieldoffsets

Add fieldoffsets(DataType)
Update README.windows.md
Revert "Fix inv for triangular matrices"

This reverts commit 247af6bd28773243e9a7dc8437cf1d3780688603.
Revert "Fix #3622"

This reverts commit c339b44a372cc996563a59c50f961eda979632c0.
Fix inv for triangular matrices
use var name LIBOPENBLAS_PATH while using system libopenblas
Alternative fix to #3594
Merge pull request #3629 from amitmurthy/amitm/ptest

Alternative fix to #3594