Add --enable-latest-deps to configure

This option make 'rebar get-deps' command to always fetch latest versions
of deps that are developed together with ejabberd instead of using frozen
commit/branch/tag.

configure.ac

@@ -211,6 +211,14 @@ AC_ARG_ENABLE(lager,
   *) AC_MSG_ERROR(bad value ${enableval} for --enable-lager) ;;
 esac],[if test "x$lager" = "x"; then lager=true; fi])
 
+AC_ARG_ENABLE(latest_deps,
+[AC_HELP_STRING([--enable-latest-deps], [makes rebar use latest commits for dependences instead of tagged versions (default: no)])],
+[case "${enableval}" in
+  yes) latest_deps=true ;;
+  no)  latest_deps=false ;;
+  *) AC_MSG_ERROR(bad value ${enableval} for --enable-latest-deps) ;;
+esac],[if test "x$latest_deps" = "x"; then latest_deps=false; fi])
+
 AC_CONFIG_FILES([Makefile
 		 vars.config
 		 src/ejabberd.app.src])
@@ -255,6 +263,7 @@ AC_SUBST(iconv)
 AC_SUBST(debug)
 AC_SUBST(lager)
 AC_SUBST(tools)
+AC_SUBST(latest_deps)
 AC_SUBST(CFLAGS)
 AC_SUBST(CPPFLAGS)
 AC_SUBST(LDFLAGS)

rebar.config

@@ -32,6 +32,22 @@
         {if_var_true, tools, {meck, "0.8.2", {git, "https://github.com/eproxus/meck", {tag, "0.8.2"}}}},
         {if_var_true, redis, {eredis, ".*", {git, "git://github.com/wooga/eredis"}}}]}.
 
+{if_var_true, latest_deps,
+ {floating_deps, [p1_logger,
+                  cache_tab,
+                  p1_tls,
+                  p1_stringprep,
+                  p1_xml,
+                  esip,
+                  p1_stun,
+                  p1_yaml,
+                  p1_utils,
+                  p1_mysql,
+                  p1_pgsql,
+                  p1_pam,
+                  p1_zlib,
+                  p1_iconv]}}.
+
 {erl_opts, [nowarn_deprecated_function,
             {if_var_true, roster_gateway_workaround, {d, 'ROSTER_GATWAY_WORKAROUND'}},
             {if_var_match, db_type, mssql, {d, 'mssql'}},

vars.config.in

@@ -45,6 +45,8 @@
 {libdir, "{{release_dir}}/lib"}.
 {docdir, "{{release_dir}}/doc"}.
 
+{latest_deps, @latest_deps@}.
+
 {ldflags, "@LDFLAGS@"}.
 {cflags, "@CFLAGS@"}.
 {cppflags, "@CPPFLAGS@"}.