grc/constants.py : BEGINNING_E > INITIAL_E
two new constants in grc/constants.py : INITIAL_A, INITIAL_ETA
two new constants in grc/constants.py : INITIAL_AI, INITIAL_ETA_IOTASUB
new constant in grc/constants.py : ETA
new constants in grc/constants.py : INITIAL_OMEGA_IOTASUB, INITIAL_OI
new constant in grc/constants.py : INITIAL_O
new constants in grc/constants.py : INITIAL_OMEGA
new function : OrthoPhoneGRC.get_the_phonetic_initial_vocalic_breathing() + tests
new function : OrthoPhoneGRC.remove_any_initial_vocalic_breathing() + test