Adding a foundation for unit tests

TODO.md

@@ -9,4 +9,18 @@
 * Create ~/.panoramix/ to host DB and config, generate default config there
 * Reintroduce query and stopwatch
 * Sort tooltip
-* Add a "Test Connection" button in Add Connection menu
+* Make "Test Connection" test further
+* Consistent colors for same entities
+* Contribution to total
+* Arbitrary expressions
+    * Group bucketing
+* ToT
+* Layers
+
+## Test
+* Line types
+* Intelligence around series name
+* Shapes
+* Line highlighting - draw attention
+
+## Bug