Fix tests to work when recode has not yet been installed.
https://github.com/rrthomas/recode/issues/12
--- tests/Makefile.in.orig 2018-09-24 15:06:05.000000000 -0500
+++ tests/Makefile.in 2018-09-26 02:16:48.000000000 -0500
check-local: Recode@pyextext@
if test -n "$(VALGRIND)"; then export VALGRIND='$(VALGRIND) --suppressions=$(srcdir)/valgrind-python.supp'; fi; \
export LD_LIBRARY_PATH=$(top_builddir)/src/@objdir@; \
+ export DYLD_LIBRARY_PATH=$(top_builddir)/src/@objdir@; \
RECODE=$(top_builddir)/src/recode$(EXEEXT) PYTHONPATH=.:$(srcdir) \
$$VALGRIND $(PYTHON) $(srcdir)/pytest $(LIMIT) $(srcdir)/t*.py