Update syncthing to 0.11.15
Update syncthing to 0.11.15

jakirkham/dockerfiles,adammcarth/dockerfiles,atyenoria/dockerfiles,atyenoria/dockerfiles,rot26/dockerfiles,rot26/dockerfiles,rot26/dockerfiles,adammcarth/dockerfiles,pmav99/dockerfiles,pmav99/dockerfiles,atyenoria/dockerfiles,jakirkham/dockerfiles,adammcarth/dockerfiles,rot26/dockerfiles,pmav99/dockerfiles,jakirkham/dockerfiles,adammcarth/dockerfiles,atyenoria/dockerfiles,jakirkham/dockerfiles,jakirkham/dockerfiles,pmav99/dockerfiles