[DOC] add a roadmap

closes #347

roadmap.md

@@ -0,0 +1,47 @@
+# 🦉 OWL Roadmap 🦉
+
+- Current version: 0.23.0
+- Status: mostly stable
+
+This roadmap is only an attempt at predicting Owl's future.  Everything may
+change!
+
+### October 2019
+
+We plan to complete the following tasks:
+
+- make owl asynchronous rendering rock solid (issue #330),
+- improve API for root widgets (issue #306),
+- replace `t-keepalive`, `t-asyncroot` and maybe `t-transition` by components (issue #295).
+
+### November 2019
+
+Once the previous tasks are done, release version 1.0alpha. This means that the
+API should be stable.  But it could change a little bit if we need it for our
+work on Odoo.
+
+### End of 2019
+
+Release v1.0
+
+- API should be stable,
+- we will use semantic versioning,
+- we will maintain a changelog and an upgrade guide.
+
+### 1.x
+
+- add chrome and firefox devtools,
+- add support for single file components,
+- fix every bugs,
+- improve documentation,
+- small backward compatible improvements.
+
+### 2.x (2021? 2022?)
+
+Maybe:
+
+- reimplement vdom to use *block* system, like Vue 3,
+- refactor `QWeb` to use an intermediate representation (some kind of AST) to
+  allow additional optimisations.
+
+