fix #5154 (nested for loop syntax & break behavior)
Windows: download busybox-win32 during make win-extras

copy it to echo.exe and printf.exe during make dist
This allows test/spawn.jl to succeed on Windows, since echo and printf
are only included as shell scripts in msysgit (and an echo.bat in
contrib/windows), but libuv cannot spawn shell or bat scripts.
Add a string constructor to VersionNumber

I feel this is more natural than `convert(VersionNumber, mystring)`, but maybe there was a design reason behind this
Do not include JIT.h header file on MCJIT builds.

Minor cleanup.
Fix and test var edge cases for zero and one-element iterables
Adds explicit Rational{BigInt} convert method. Indirectly addresses #6712.
add checked integer truncation intrinsics
Merge branch 'master' of github.com:JuliaLang/julia
Merge pull request #7500 from crayxt/patch-2

Do not include JIT.h header file on MCJIT builds.
Clarify error text in REPL when encountering an uncaught MethodError

Discussion: https://github.com/JuliaLang/julia/pull/7497
Add consistent single space after each comma in replutil.jl
change comprehension lowering to trust only length() for iteration. fixes #7427
Merge branch 'master' of github.com:JuliaLang/julia
make circshift more type stable; fixes #7503
Set --check-bounds=yes for runtests.jl workers
improve subtypes() to look at parameters and exclude aliases. fixes #7443
Merge pull request #7494 from JuliaLang/sjk/check_bounds

Disable atsign-inbounds when running tests
Add check for zero-length input in sparsevec. Fix #7507
Patch pcre to pass all tests when compiled with GCC 4.9.

Pcre failed to pass one test when compiled with GCC 4.9.
Patch taken from Fedora, original url is
http://pkgs.fedoraproject.org/cgit/pcre.git/plain/pcre-8.35-Do-not-rely-on-wrapping-signed-integer-while-parsein.patch
Checked on Linux 64-bit with GCC 4.7, 4.8, 4.9, Clang 3.5 - all good.
simpler parsing of multi-range for