emacs requires \Unnnnn unicode escapes to be padded to 8 hex digits
some FreeBSD fixes (closes #8053)
Fix vectorized DateTime parser to use ISODateTime format instead of ISODateFormat
Clean out old openblas checksums
Some libcxx-related makefile tweaks
Windows CI using AppVeyor

New configuration file appveyor.yml
- Downloads and installs latest Julia binary, uses it for dependency libraries
- Also uses MSYS from bundled Git installation

Build script contrib/windows/msys_build.sh
- Downloads MinGW, LLVM, make, etc
- Sets up Make.user to use as many downloaded dependencies as possible
Use msys with a different mingw build, cleaner method for silent downloads

Clean up the MSVC side of the build script

Rehost cut-down MSVC LLVM binary
Update for removal of readline and renaming of julia exe

Remove incompatible pre-installed mingw from AppVeyor path

Force tests to run in parallel

Use compile and ar-lib from libuv for MSVC
update nightly download location

dont try to run tests in parallel
update msys_build.sh for build changes and mojibake
handle difference between windows and linux p7zip

set MARCH correctly
add -MD flag for msvc standard library
extract pcre_h.jl from nightly
use msvc 2013 version of llvm (still need to build a 32 bit version of this)
libuv static lib and headers are not in nightly any more