Update ams1, ams2, fra2 ans sin1 nodes

Hey, bad news: Melbicom and Terrahost aren‘t able or willing to handle that much prefix updates every day. Just to dynamic and causing a lot of issues. Thus, ams2.nl (14.10.), osl1.no (14.10.) fra2.de and sin1.gp (26.10.) will be closed for all services. Alternative providers highly welcome.

jo