tree-wide: remove Emacs lines from all files This should be handled fine now by .dir-locals.el, so need to carry that stuff in every file.

sd-ndisc: introduce separate callbacks As the data passed is very different, we introduce four different callbacks: - Generic - router discovery timed out or state machine stopped - Router - router and link configuration received - Prefix onlink - configuration for an onlink prefix received - Prefix autonomous - configuration for to configure a SLAAC address for a prefix received

sd-ndisc: notify user on STOP Also, stop the state machine when we get into a broken state, rather than just notify the user.

util-lib: split our string related calls from util.[ch] into its own file string-util.[ch] There are more than enough calls doing string manipulations to deserve its own files, hence do something about it. This patch also sorts the #include blocks of all files that needed to be updated, according to the sorting suggestions from CODING_STYLE. Since pretty much every file needs our string manipulation functions this effectively means that most files have sorted #include blocks now. Also touches a few unrelated include files.

sd-ndisc: drop sd_ndisc_get_prefixlen() This is unused, and in the future we will pass prefixes and prefixlengths directly to the callbacks when needed rather than having to search for them.

libsystemd-network: split icm6-util.[ch] out of dhcp6 code

sd-ndisc: rename API from sd-icmp6-nd

sd-icmp6-nd: rename files to sd-ndisc The actual code rename will follow. The reason for the change of name is to make it simpler and more uniform with how we name other libraries (we don't include the underlying protocol). The new name also matches the naming in the kernel (which is particularly relevent here as we expect to let the kernel do some parts of the protocol and we do others).