Add a monitor module to save tracking data based on h5py
Bunch Monitor is used to get statistics from a specific bunch
PhaseSpaceMonitor is used to save the phase space of a specific bunch
For now the .hdf5 file is opened and closed at each write operation, this seems to cause some problems for mpi.

Update machines/__init__.py, machines/soleil.py, tracking/__init__.py, tracking/aperture.py, tracking/element.py, tracking/optics.py, tracking/parallel.py, tracking/particles.py, tracking/rf.py, tracking/synchrotron.py files

CircularAperture, ElipticalAperture and RectangularAperture elements are added

To be PEP8 complient:
Lowercase folders
Extended docstrings
Rename and divide some files

Add synchrotron radiation in transverse plane
Fix a mistake in the transverse one turn map

New parallel module to handle Mpi class which is used in Beam

Test OK, to improve

ring.L instead of ring.L0

Add bunch_X properties to Beam class
Add a generator over "not empty" bunches to Beam class
Modify Bunch class in order to have mean, std and emit as property and not method

Empty bunches are now not None any more but represented by Bunch class with 1 mp set to dead
Change init_beam to reflect the change

Empty bunches are now not None any more but represented by Bunch class with 1 mp set to dead
Change init_beam to reflect the change

Use pandas DF to hold data in Bunch class instead of numpy masked array -> better behaviour and allows to set to alive particles only