Removed completed TODOs.

Snakefile

@@ -34,9 +34,7 @@ TODO: Ask whether Burgers has compatible ICs other than Sine and
 
 Urgent:
 TODO: Add Burgers class completely
-TODO: Clean up exact solution for Burgers -> Done
 TODO: Enabale choice of equation
-TODO: Adapt code to accommodate boundary decorator -> Done
 TODO: Add subclasses of Burgers
 TODO: Ignore ghost domains by flagging all cells with it for extreme outlier
 TODO: Add functions to create each object from dict