Preparation of draft-ietf-ccamp-optical-impairment-topology-yang-07 f…

…or submission

- YANG model tree view updated: copied from https://github.com/ietf-ccamp-wg/draft-ietf-ccamp-optical-impairment-topology-yang/blob/master/ietf-optical-impairment-topology.tree

- YANG code updated: copied from https://github.com/ietf-ccamp-wg/draft-ietf-ccamp-optical-impairment-topology-yang/blob/master/ietf-optical-impairment-topology.yang

- New Table 1 entry added for ietf-layer0-types-ext

- Some editorial changes

Co-Authored-By: Esther Le Rouzic <EstherLerouzic@users.noreply.github.com>
Co-Authored-By: Gabriele Galimberti <14770864+ggalimba56@users.noreply.github.com>
Co-Authored-By: sergiobelotti <sergio.belotti@nokia.com>
Co-Authored-By: italobusi <12461741+italobusi@users.noreply.github.com>