add jl_get_cpu_name function to libjulia

thin ccall'able wrapper around llvm::sys::getHostCPUName
Modify jl_get_cpu_name to use jl_pchar_to_string,

add Sys.cpu_name
Move cpu_name into init_sysinfo()
Add back llvmcall
Import update llvmcall from cxx branch
Fix build for non-MCJIT versions of Julia & Add tests
Simple implementation of chmod(path, mode)

currently only integer modes, can do string modes like +x later
fixes #7574
Allow deletion of read-only files on Windows
Remove type constraints from intersect(::StepRange,::StepRange). This allows any range type where the step type implements lcm(), gcdx(), and mod() to use the method definition.
Revamp netload tests to more verbose and resiliient style
Fix nettest to run on multiple workers again
Whoops, accidentally reduced test case size
Improve performance of A_ldiv_B! for QR factorizations. Fixes #7887.

To get really good performance we need faster array views.
LLVM Patch to fix #7911
Revert "Boundschecks for searchsorted & remove step(r::Range)==0 tests"

This reverts commit 10e51e5bcfb35a3a159ecf4934c3f074900f844e.

Originally merged by 2d5dbf35b63e0fae9a741184bc27c53493d7474c, this is
incorrect in a number of ways.

The searchsorted* methods with explicit lo and hi indices are an not
part of the public API for these functions. Thus, the correctness of
the bounds given don't need to be checked – that is up to the caller.
If we decide to expose the ability to call searchsorted* with explicit
start and end indices, there should be a better API for that which
doesn't require passing an Ordering object and which checks bounds.

In particular, this broke the old behavior of searchsorted when the
value that's being searched for is not in the array. Fix #7916. Also
added somes tests to make sure this doesn't regress again.

At the time this was committed, I think that ranges could actually
have a zero step – there was a reason for that check to be there.
This may no longer be the case, but since it's cheap to check, we may
as well handle it correctly and decouple the correctness of the
sorting functions from a detail of the range implementation.

Conflicts:
	base/sort.jl
utf8proc -> libmojibake (closes #7656, fixes #7582)
Merge pull request #7912 from JuliaLang/kf/7911

LLVM Patch to fix #7911
added unicode shortcut documentation
Merge branch 'master' into unicodedocs
Change the last two args of split/rsplit to 'limit' and 'keep' keywords. Fixes #6412