Ntfy Versions Save

• termux backend
• ruamel.yaml > 0.15 support

• readds pyobc dependency on macosx
• fix homedir ~ substitution
• doesn't throw errors if $WINDOWID isn't set
• escape & in linux notifications"

• Disable PyObjC dep to allow install on MacOS 10.12
• use yaml.safe_load to avoid warnings.

• Instapush support (@giuseongit)
• Slack support (@juanpabloaj)
• Prowl support (@sambrightman)
• Syslog support (@jlesage)
• MacOS & shell-integration bugfixes (@eykd)

• Simplepush backend (@tymm)
• Fix ntfy done --pid regression (@AilisObrian)
• Allow specifying title per-backend in the config
• Notifico! support (@eightnoteight)
• Fix bug with homedir shortening (@eightnoteight)
• Disable homedir shortening on Windows (@avamsi)
• internal cleanup (@avamsi)
• add missing PyObjC dependency for MacOS (@dcoeurjo)

• docs updates
• looser ruamel.yaml requirements
• urgency level for ntfy done (including shell integration) on linux
• checking of config params via introspection of backends
• pushjet support (from @schwert)

Thanks to @rahiel.

Fully fixes shell-integration regressions. Thanks a lot to @rcaloras.