Optimization toolbox fmincon() instead of Rasmussen's minimize() - first version
Chagnes which should go into the **master**

- gpedaStep2d.m -- better plotting of POI
- cmaes.m -- accepts function handles as well (not just strings)
- modelInit -- better covariance function parameters initialization
- stopTolX -- correction of missing semicolon

- myslicesample.m
- sampleSlice.m
- stopLowLogpdf.m -- possibility to stop when POI drops too low