redraw axes in utils.draw
Axis min and max setter/getters
clean up
Merge pull request #589 from ndawe/master

Axis min and max setter/getters
root2hdf5: loop on sorted trees
Merge pull request #590 from ndawe/master

root2hdf5: loop on sorted trees
improve Efficiency
Merge pull request #591 from ndawe/master

improve Efficiency
Efficiency: fix handling of overflow
Merge pull request #592 from ndawe/master

Efficiency: fix handling of overflow
root2hdf5: create tree2hdf5 function and add --ignore-exception option
Merge pull request #593 from ndawe/master

root2hdf5: create tree2hdf5 function and add --ignore-exception option