Created an excel file (open document) format to test the heat model.
Merge https://github.com/larics/assisi-playground into heat
Renamed folders where excel heat is.
Reformated code in AbstractGridSimulation
Added some rules to .gitignore
Added playground.cfg
Corrected .gitignore cmake rules
Merge branch 'master' of https://github.com/larics/assisi-playground into heat
First implementation of a mesh heat actuator.
Need visualization to test it.
Merge pull request #17 from plsm/heat

Merging Pedro's changes: excel heat model (for evaluating the model), mesh heat actuator. Fixes #26.