* srfi/srfi-37.scm.in: New file, taken from Guile 2.0.9.
* m4/guix.m4: New macro.
* configure.ac: Use it. Define Automake conditional `INSTALL_SRFI_37'.
* Makefile.am (nobase_nodist_guilemodule_DATA)[INSTALL_SRFI_37]: Add
srfi/srfi-37.scm.
(GOBJECTS)[INSTALL_SRFI_37]: Add srfi/srfi-37.go.
(srfi/srfi-37.scm)[INSTALL_SRFI_37]: New target.
(EXTRA_DIST): Add srfi/srfi-37.scm.in.
* guix/derivations.scm: Export `read-derivation' and `write-derivation'.
* srfi/srfi-64.scm, srfi/srfi-64.upstream.scm: New files, from libchop.
* tests/derivations.scm, tests/test.drv: New files.