Calculation was wrong for off center beams.

Now works correctly for up to date version of seaborn.

Added class representation for ComplexData, Impedance, WakeFunction, WakeField and Beam classes.
Rework the deconvolution/from_wakepotential/to_impedance methods for them to work with any data loaded in the Impedance/WakeFunction classes and not just CST text files.
Add a plot method for the Impedance/WakeFunction classes.
Improved WakeField class by adding __iter__ and __add__ methods.
Add a read_ECHO2D function.

Save and load methods allow to save Bunch and Beam object and reload them later on.
Load method for Beam allow to choose if mpi is used or not.
Initial modification from Watanyu.

Add Courant Snyder invariant monitoring in BeamMonitor
Add a bunch_cs method to Beam

move down init

Add a is_empty property to the Bunch class.
Add a check_empty optional parameter to the Monitor.track_bunch_data method.
ProfileMonitor: if the bunch is empty, no profile is saved.
WakePotentialMonitor: if the bunch is empty, the same from last good turn is saved.
BunchSpectrumMonitor: if the bunch is empty, the incoherent spectrum is nan.

Beam.mpi_share_distributions is now moved to mpi.share_distribution
Now mpi4py is only needed for the multi-bunch tracking and not for single bunch

bunch_index returns the array with the positions (index) of the non-empty bunches, to be used with Beam.not_empty iterator.
bunch_mean, bunch_std and bunch_emit now iterate only over non empty bunches.

CavityResonator.init_phasor is now CavityResonator.init_phasor_track
New CavityResonator.init_phasor uses analytic formula
Fix phase slipping factor for initialization case (rf frame should be delta = (self.wr - self.m*self.ring.omega1))

fix init

Fix mpi_share_distributions

This avoid to store a huge amount of data in all cores before calling mpi_init to share it to all the cores.

Wrong data shared in Beam.mpi_share_distributions
Old names in CavityResonator.track corrected

Change back invariant name to cs_invariant
Simplify SkewQuadrupole track method

Not needed any more due the SynchrotronRadiation change.

Fix bug on Beam.distance_between_bunches for the last bunch when the first bunches are empty.
Change Beam.distance_between_bunches to compute the array only at initalization with Beam.update_distance_between_bunches
Beam.mpi_share_distributions can now share all bunch dimensions.

Typo in the type of data to share for bunch profile. Not sure if there was an effect.

In track method of cavity resonator, there was an additional phasor decay of bin length.
To avoid that the good boundaries are set bins[0] instead of center[0].
For now the bins are also shared in Beam.mpi_share_distributions

Add tracking to CavityResonator based on the mbtrack implementation but using a analytic formula for speed-up
Add method to Beam to share longitudinal distributions
Add methods to Mpi to look for next and previous bunches
Add start of a CavityMonitor, to improve to deal with multi-cores

- cs_invariant method in Bunch is renamed to 'action'.
- Action is now saved together with BunchMonitor and can be plotted in plot_bunchdata

Update docstrings
Use pd.DataFrame representation for bunch __repr__
Add the track_alive option for Bunch and Beam.init_beam

1st test, not complete

Remove tools.py to avoid circular import problem with wakefield.py -> merged into wakefield.py
Remove machines folder to save machine data in a seperate git instance
Rework import so the code can be used as independant module mbtrack2

Plotting routines now return figure object.

Rebase test_plot on master
plot_phasespacedata -> only "particles" dataset is plotted
plot_phasespacedata -> mandatory arguments

- total_size and save_every input parameters have been removed.
- only_alive option function has been changed
- Some small corrections on scaling of delta, bunch_charge, bunch_current

- "plot_bunchdata" and "plot_phasespacedata" have been separated from particles module.
- Input prompt has been removed from the code.
- Plotting method for variables in Beam object such as "bunch_current" and "bunch_charge" with respect to bunch number has been added.
- Only alive particles plotting option has been added.

Two plotting methods, "plot_bunchdata" and "plot_phasespacedata", have been added to Beam class.
"getplot" method in Bunch class has been modified and renamed to "long_phasespace".

Phase space plotting method was added

Filling_pattern update should happen before no_empty is used !

- total_size and save_every input parameters have been removed.
- only_alive option function has been changed
- Some small corrections on scaling of delta, bunch_charge, bunch_current

Add T1 = RF period to synchrotron object
Add binning and plot_profile to Bunch object // plot_profile to improve
Modify beam.filling_pattern to store the array instead of computing it every time
Add distance_between_bunches method to Beam object
Modify not_empty method of Beam to use filling_pattern

- "plot_bunchdata" and "plot_phasespacedata" have been separated from particles module.
- Input prompt has been removed from the code.
- Plotting method for variables in Beam object such as "bunch_current" and "bunch_charge" with respect to bunch number has been added.
- Only alive particles plotting option has been added.