gnu: julia: Upgrade to 1.3.1.

gnu: julia: Upgrade to 1.3.1.

* gnu/packages/julia.scm (libuv-julia): Upgrade to 2.0.0-1.35b1504.
(libunwind-julia): New variable.
(llvm-patch): Rename to ...
(julia-patch): ... this. Update to 1.3.1.
(llvm-julia): Adjust patch-set based on above change. Adjust indent.
(julia): Update to 1.3.1.
[source]: Add patch.
[arguments]: Adjust custom 'prepare-deps (llvm-patch): Rename to ...
(julia-patch): ... this. Update to 1.3.1.
(llvm-julia): Adjust patch-set based on above change.
(julia): Upgrade to 1.3.1.
[arguments]: Adjust custom 'prepare-deps phase based on changed inputs.
Remove most of 'hardcode-soname-map. Adjust 'fix-include-and-link-paths.
Add new 'fix-precompile phase. Adjust custom 'disable-broken-tests
phase. Add new 'make-wrapper phase. Adjust make-flags.
[inputs]: Add p7zip, mbedtls-apache, curl libssh2.
Remove openspecfun, fftw, fftwf, python2-virtualenv, rmath.
Replace libunwind with libunwind-julia, custom suitesparse with system
suitesparse, custom dsfmt with system dsfmt.
[native-search-paths]: Add JULIA_DEPOT_PATH.
* gnu/packages/patches/julia-SOURCE_DATE_EPOCH-mtime.patch: New file.
* gnu/local.mk (dist_patch_DATA): Register it.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>