implemetend in the package.
A lot of files has been modified because some of the internal syntax has
changed. But the top level methods should still work.

Two tests about the plots of synchronized oscillatory simulations have
been added.

All tests passed.

- A_per (period_automaton) computes noisy period of an oscillatory model
- A_eucl (euclidean_distance) computes euclidean distance with regard to
data points of a trajectory.

1 script that plots oscillatory trajectory is added