feat(mako): mako-render generates output dirs

That way, the makefile doesn't need to know that much anymore, and
gets simpler/less verbose.

\# Also
* Added filters for rust doc string
* fixed .PHONY

src/mako/lib/util.py

@@ -1,3 +1,13 @@
+
+# rust module doc comment filter
+def rmdc(s):
+    return '//! ' + s
+
+# rust doc comment filter
+def rdc(s):
+    return '/// ' + s
+
+# Expects v to be 'v\d+', throws otherwise
 def to_api_version(v):
 	assert len(v) >= 2 and v[0] == 'v'
 	return v[1:]