Add output directory for generated EDoc

plugins/edoc.mk

@@ -7,12 +7,13 @@
 
 EDOC_OPTS ?=
 EDOC_SRC_DIRS ?=
+EDOC_OUTPUT ?= doc
 
 define edoc.erl
 	SrcPaths = lists:foldl(fun(P, Acc) ->
 		filelib:wildcard(atom_to_list(P) ++ "/{src,c_src}") ++ Acc
 	end, [], [$(call comma_list,$(patsubst %,'%',$(EDOC_SRC_DIRS)))]),
-	DefaultOpts = [{source_path, SrcPaths}, {subpackages, false}],
+	DefaultOpts = [{dir, "$(EDOC_OUTPUT)"}, {source_path, SrcPaths}, {subpackages, false}],
 	edoc:application($(1), ".", [$(2)] ++ DefaultOpts),
 	halt(0).
 endef
@@ -31,4 +32,4 @@ edoc: distclean-edoc doc-deps
 	$(gen_verbose) $(call erlang,$(call edoc.erl,$(PROJECT),$(EDOC_OPTS)))
 
 distclean-edoc:
-	$(gen_verbose) rm -f doc/*.css doc/*.html doc/*.png doc/edoc-info
+	$(gen_verbose) rm -f $(EDOC_OUTPUT)/*.css $(EDOC_OUTPUT)/*.html $(EDOC_OUTPUT)/*.png $(EDOC_OUTPUT)/edoc-info