adds more assessory and implements all optional chars

added more accessories

Merge branch 'ip-camera'

Merge branch 'tv' brutella#132

Remove the model interface and import characteristics/services from m…

…etadata file

There was no benefit in using the model interface in contrast to the actual structs
and their public fields. Therefore the model package is removed. This changes the
import paths of the accessory/service/characteristic packages, which are now in the
library's root directory.

Also the code for all services and characteristics is now auto-generated by importing
the data from the metadata plist file in the HAPAccessoryKit.framework (see gen and
cmd package). We can now import new types more easily in the future.

Existing code should migrate to the new version by replace import paths containing
github.com/brutella/hc/model* with github.com/brutella/hc/*

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