Use non-sourceforge download for pcre

sourceforge is the worst, I'd rather use ftp than deal with how often it's down

plus the backup caching server we use has been having some issues lately

Author: tkelman

deps/Makefile

@@ -740,7 +740,7 @@ PCRE_SRC_TARGET = pcre2-$(PCRE_VER)/.libs/libpcre2-8.$(SHLIB_EXT)
 PCRE_OBJ_TARGET = $(build_shlibdir)/libpcre2-8.$(SHLIB_EXT)
 
 pcre2-$(PCRE_VER).tar.bz2:
-	$(JLDOWNLOAD) $@ http://sourceforge.net/projects/pcre/files/pcre2/$(PCRE_VER)/$@/download
+	$(JLDOWNLOAD) $@ ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre2-$(PCRE_VER).tar.bz2
 pcre2-$(PCRE_VER)/configure: pcre2-$(PCRE_VER).tar.bz2
 	$(JLCHECKSUM) $<
 	$(TAR) jxf $<