move Runtime{State,Lchan} from pySim.filesystem to new pySim.runtime

Those two are really separate concepts, so let's keep them in separate
source code files.

Change-Id: I9ec54304dd8f4a4cba9487054a8eb8d265c2d340
diff --git a/pySim-trace.py b/pySim-trace.py
index ba1568c..d457bf4 100755
--- a/pySim-trace.py
+++ b/pySim-trace.py
@@ -6,7 +6,7 @@
 from pprint import pprint as pp
 
 from pySim.apdu import *
-from pySim.filesystem import RuntimeState
+from pySim.runtime import RuntimeState
 
 from pySim.cards import UiccCardBase
 from pySim.commands import SimCardCommands