Adapt sim_* cfg's to current syntax

+ make 'limit' usable as type in cfg files
+ minor fixes

Change-Id: Ib94b2645c7a0d978d64d4c86c4415d4b5b0d485f
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21485
Tested-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>

cfg/sim.cfg

@@ -13,7 +13,7 @@ bindport=10767
 class=secop.simulation.SimDrivable
 .description=simulation stuff
 .extra_params=param3,param4,jitter,ramp
-param3.datatype=['bool']
+param3.datatype={"type":"bool"}
 param3.default=True
 param3.readonly=False
 jitter.default=1