Support canonical URLs

Signed-off-by: José Valim <[email protected]>

Author: José Valim

Makefile

@@ -1,6 +1,7 @@
 REBAR ?= "$(CURDIR)/rebar"
 PREFIX ?= /usr/local
 DOCS := v1.2
+CANONICAL := stable
 ELIXIRC := bin/elixirc --verbose --ignore-module-conflict
 ERLC := erlc -I lib/elixir/include
 ERL := erl -I lib/elixir/include -noshell -pa lib/elixir/ebin
@@ -128,7 +129,7 @@ clean_exbeam:
 
 LOGO_PATH = $(shell test -f ../docs/logo.png && echo "--logo ../docs/logo.png")
 SOURCE_REF = $(shell head="$$(git rev-parse HEAD)" tag="$$(git tag --points-at $$head | tail -1)" ; echo "$${tag:-$$head}\c")
-COMPILE_DOCS = bin/elixir ../ex_doc/bin/ex_doc "$(1)" "$(VERSION)" "lib/$(2)/ebin" -m "$(3)" -u "https://github.com/elixir-lang/elixir" --source-ref "$(call SOURCE_REF)" $(call LOGO_PATH) -o doc/$(2) -p http://elixir-lang.org/docs.html $(4)
+COMPILE_DOCS = bin/elixir ../ex_doc/bin/ex_doc "$(1)" "$(VERSION)" "lib/$(2)/ebin" -m "$(3)" -u "https://github.com/elixir-lang/elixir" --source-ref "v$(VERSION)" $(call LOGO_PATH) -o doc/$(2) -a http://elixir-lang.org/docs/$(CANONICAL)/$(2)/ -p http://elixir-lang.org/docs.html $(4)
 
 docs: compile ../ex_doc/bin/ex_doc docs_elixir docs_eex docs_mix docs_iex docs_ex_unit docs_logger