rt_loop: act on rm changes in whole neighborhood
rt_loop: act on rm changes in whole neighborhood

next_hop() now uses the neighborhood from the rm (before: neighborhood from
dht_node_state). But the rm neighborhood was only updated when the self, succ
or pred changed. Now the neighborhood is updated on every change, allowing
next_hop to still use the whole list of preds and succs for routing decisions.

jvf/scalaris,scalaris-team/scalaris,caijieming-baidu/scalaris,jvf/scalaris,jvf/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,caijieming-baidu/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,jvf/scalaris,caijieming-baidu/scalaris,caijieming-baidu/scalaris,caijieming-baidu/scalaris,jvf/scalaris,caijieming-baidu/scalaris,caijieming-baidu/scalaris,jvf/scalaris,scalaris-team/scalaris,scalaris-team/scalaris,jvf/scalaris