link libjulia with -lz, but not necessarily the julia executable
ref #4742
bring back --system-libs for LLVM >= 3.4
a change I needed to make USE_LLVM_SHLIB work
use llvm-config --ldflags both before and after --libs
Add LLDB_DISABLE_PYTHON flag to build lldb without python
disable LLVM's signal handling

now we can avoid compilation in jl_get_builtin_hooks

ref commit 8a1988ba8f7ca6434ea21720b251d18606a39d18
Merge branch 'master' of github.com:JuliaLang/julia
Get variants take Callable defaults rather than Functions
Merge pull request #7717 from garborg/getcallable

RFC: Get variants take Callable defaults rather than Functions
only define fallback .+ and .- for Number. fixes #7708
Merge branch 'master' of github.com:JuliaLang/julia
Merge pull request #7696 from JuliaLang/jb/fixlibzlink

make sure libjulia is linked against libz
Fix issue #7687, by revising original fix for issue #41
to use volatile store/load on 32-bit x86 only.
DisablePretty went away in LLVM v3.4 and is disabled by default
Merge pull request #7718 from jakebolewski/jcb/disable_pretty_fix

DisablePretty went away in LLVM v3.4 and is now disabled by default
remove the slow scalar reinterpret that used a 1-element array

improve box() to catch size mismatches with pointer types

fix an issue in box() with a non-leaf-type; it would incorrectly
create an object reference, leading to a segfault. ideally,
allocate_box_dynamic should do a run-time check for non-leaf types if
it might be necessary, but for now just check isbits() in reinterpret.

fixes #7697
Merge pull request #7719 from ArchRobison/adr/fpext

Fix issue #7687, by revising original fix for issue #41
expose OPENBLAS_NO_AVX2 option

ref #7476
tweak readme no_avx -> no_avx2
addprocs: wait till all workers are connected to each other.