docs: Add initial timeline

images/3-4_project_plan.mmd

 gantt
-	title OpenSCENARIO 2.0 Project Plan
+	title ASAM Test Specification Study Group Plan
 	dateFormat  YYYY-MM-DD
-	section Domain Model
-        Core Domain Model:a1, 2020-06-01, 270d
-        Extensibility Guidelines:2021-01-01,120d
-        Ontology:2020-06-01, 300d
-
-	section DSL
-        Decide on a DSL foundation for OSC:2020-06-01,120d
-        Datatypes (basic):2020-07-01,120d
-        Datatypes (compound):2020-07-01,180d
-        Expressions:2020-11-01,90d
-        Semantics:2020-12-01,120d
-        Libraries:2020-11-01,120d
-        Language Reference Manual:2020-12-01,150d
-
-	section Usage & Pragmatics
-        Scenario Creation Workflow Guidelines:2020-06-01,240d
-        Abstraction/Concretization Guidelines for DSL:2020-06-01,120d
-        Library Concepts:2021-01-01,150d
-        Test Design Workflow:2020-11-01,180d
-
-	section Feature Subset
-        Concept:f1,2020-06-01,120d
-        Definition:f2,after f1,90d
-        Validation:after f2,60d
-
-	section Coordination
-        Migration guidelines 1.x <-> 2.0:2021-01-01,120d
-
-	section Review        
-        Project :crit,2021-04-01,30d
-        Public :crit,2021-05-01,31d
-        Release:crit,2021-06-01,30d
\ No newline at end of file
+  axisFormat  %b-%y
+  section Deliverables
+    Define use cases:2020-11-01,80d
+    Define workflows:2020-12-01,80d
+    Identify further actions:2021-01-01,60d
+    Review :milestone, m1, 2021-03-01, 1d
+    Release :milestone, m2, 2021-03-23, 1d
+  section Collaboration
+    Identify partners:a1, 2020-11-01, 20d
+    Setup agreements:after a1,20d

subchapters/3-4_timeline.adoc

@@ -5,3 +5,4 @@ endif::[]
 === Timeline
 The work packages shall be carried out as per the following time schedule:
 
+image::3-4_project_plan.svg[]
\ No newline at end of file