Update Mac juliarc.jl (fixes #6880)

git (bundled in ROOT/libexec/git-core) isn't included on the PATH used by Julia. This causes issues on OSX when using the package manager because GIT_EXEC_PATH does point to the bundled git tools. By adding git-core explicitly, all issues are fixed. The bundled git is used throughout.
~8% improvement in parsing speed by using a Set for op-chars
fix hashing of Char, Bool, and bitarrays

under the new isequal(), there is no clear way to hash bitarrays efficiently
Merge branch 'master' of github.com:JuliaLang/julia
Make sure SIGUSR1 is unblocked for profiler

We cannot make any assumptions about the state of the signal mask.
Turns out that the USR1 signal can be blocked by parent processes and
then the profiler will not work right (gdm is an example).  Make sure
that if we are running the profiler that the USR1 signal is unblocked.
don't make a GC root for a specialized function arg if is_stable_expr
Merge pull request #7002 from aplund/profile_sigusr1unblock

Make sure SIGUSR1 is unblocked for profiler
rearrange hash methods. probably fixes #7000

code for string Dicts was getting inferred before hash was defined for
strings. key properties like hash should be defined along with types.
Merge branch 'master' of github.com:JuliaLang/julia
Add new error code from 265c5297930fd0f036cd9282b52cccb341d3c7e7
print write failures to STDERR, if nobody is watching for them, rather than silently discarding them and closing the stream
remove specialized countnz(::AbstractArray{Bool})

the AbstractArray definition yields the exact same code
fix formatting issues caught by Jeff in 298a39d0717c485cfa247e0733e2884c06d2e259
rm U+223C (tilde operator) from infix list, since it is too similar to ASCII ~
Merge pull request #6992 from apleonhardt/apl/macgit2

Update Mac juliarc.jl (fixes #6880)
Make readdlm use_mmap false by default on windows.
fixes #4664
Merge pull request #7007 from tanmaykm/readcsv

Make readdlm use_mmap false by default on windows.
Merge pull request #7003 from JuliaLang/jb/fewer-arg-roots

RFC: don't make a GC root for a specialized function arg if is_stable_expr
Fix typo in QR multiplication