PyHEADTAIL v1.0.9

Bugfix in transverse_tracking module:
Use numpy float comparison in transverse_tracking.py and
transverse_tracking_cython.pyx to ensure that s[-1]==C.

Other float comparisons have been eliminated e.g. in the particles.py
and the generators.py modules. However, some are still present in the code
and need to be fixed (e.g. in wakes.py, tbc how).