tree-wide: group include of libudev.h with sd-*

tree-wide: sort includes Sort the includes accoding to the new coding style.

util-lib: split out syslog-related calls into syslog-util.[ch]

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.

tree-wide: remove unused functions

libudev-util: check length before accesing the array

remove unused includes This patch removes includes that are not used. The removals were found with include-what-you-use which checks if any of the symbols from a header is in use.

treewide: drop unnecessary trailing \n in log_*() calls

udev: switch to systemd logging functions

libudev: do not accept invalid log levels Invalid log levels lead to a assert failure later on. https://bugs.freedesktop.org/show_bug.cgi?id=85657

udev: util - use log_level_from_string()

libudev: util - drop util_delete_path() Use rmdir_parents() from src/shared instead.

libudev: drop util_lookup_{user,group} Use shared versions instead. Difference is with overwriting of repeated user/group name, and lack of logging.

udev - drop print_kmsg The only remaining user was 'starting version XXX', which is now logged using log_info().

Revert "libudev: use get_*_creds from shared rather than util_lookup_*" This reverts commit a56ba6158b9649e01226dfaf3ff7082c82571090. The commit was pushed in error.

libudev: use get_*_creds from shared rather than util_lookup_*

everywhere: make use of new0() and macro() macros, and stop using perror()

libudev: ship the original MurmurHash2.[ch] file

device-nodes: move device node specific code to own file In the process, rename udev_encode_string which is poorly named for what it does. It deals specifically with encoding names that udev creates and has its own rules: utf8 is valid but some ascii is not (e.g. path separators), and everything else is simply escaped. Rename it to encode_devnode_name.

move utf8 functions from libudev-private.h to utf8.h There's now some more obvious overlap amongst the two utf8 validation functions, but no more than there already was previously. This also adds some menial tests for anyone who wants to do more merging of these two in the future.

Remove some dead code Based on coverity report.

libudev: avoid potential misaligned accesses clang reports: src/libudev/libudev-util.c:665:35: warning: cast from "const unsigned char *" to "unsigned int *" increases required alignment from 1 to 4 [-Wcast-align]

use streq instead of strcmp

udev: move string copy functions to shared/

udev: net_id - append "dev_id" value if needed

libudev: update copyright headers

udev: use usec_t and now()

libudev: remove dead code

udev: avoid creating /dev/kmsg with fopen() to support CONFIG_PRINTK=n

libudev: prefix log macros with 'udev_'

docs: hook-up gtk-doc to 'make check'

udev: replace util_create_path() with mkdir_parents()

udev: use startswith() and streq()

udev: move libudev, gudev to src/; move gudev/docs/, udev/docs/ to to docs/