util: move all to shared/ and split external dependencies in separate internal libraries

Before:
  $ ldd /lib/systemd/systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fffb05ff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f90aac57000)
  libcap.so.2 => /lib64/libcap.so.2 (0x00007f90aaa53000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f90aa84a000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f90aa494000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f90aae90000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f90aa290000)
  libattr.so.1 => /lib64/libattr.so.1 (0x00007f90aa08a000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f90a9e6e000)

After:
  $ ldd systemd-timestamp
  linux-vdso.so.1 =>  (0x00007fff3cbff000)
  libselinux.so.1 => /lib64/libselinux.so.1 (0x00007f5eaa1c3000)
  librt.so.1 => /lib64/librt.so.1 (0x00007f5ea9fbb000)
  libc.so.6 => /lib64/libc.so.6 (0x00007f5ea9c04000)
  /lib64/ld-linux-x86-64.so.2 (0x00007f5eaa3fc000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007f5ea9a00000)
  libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f5ea97e4000)

1 files changed, 0 insertions, 69 deletions

diff --git a/src/set.h b/src/set.h
deleted file mode 100644
index 885780c4c0..0000000000
--- a/src/set.h
+++ /dev/null
@@ -1,69 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-#ifndef foosethfoo
-#define foosethfoo
-
-/***
-  This file is part of systemd.
-
-  Copyright 2010 Lennart Poettering
-
-  systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
-  (at your option) any later version.
-
-  systemd is distributed in the hope that it will be useful, but
-  WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-/* Pretty straightforward set implementation. Internally based on the
- * hashmap. That means that as a minor optimization a NULL set
- * object will be treated as empty set for all read
- * operations. That way it is not necessary to instantiate an object
- * for each set use. */
-
-#include "hashmap.h"
-
-typedef struct Set Set;
-
-Set *set_new(hash_func_t hash_func, compare_func_t compare_func);
-void set_free(Set* s);
-void set_free_free(Set *s);
-Set* set_copy(Set *s);
-int set_ensure_allocated(Set **s, hash_func_t hash_func, compare_func_t compare_func);
-
-int set_put(Set *s, void *value);
-int set_replace(Set *s, void *value);
-void *set_get(Set *s, void *value);
-void *set_remove(Set *s, void *value);
-int set_remove_and_put(Set *s, void *old_value, void *new_value);
-
-int set_merge(Set *s, Set *other);
-void set_move(Set *s, Set *other);
-int set_move_one(Set *s, Set *other, void *value);
-
-unsigned set_size(Set *s);
-bool set_isempty(Set *s);
-
-void *set_iterate(Set *s, Iterator *i);
-void *set_iterate_backwards(Set *s, Iterator *i);
-void *set_iterate_skip(Set *s, void *value, Iterator *i);
-
-void set_clear(Set *s);
-void *set_steal_first(Set *s);
-void* set_first(Set *s);
-void* set_last(Set *s);
-
-#define SET_FOREACH(e, s, i) \
-        for ((i) = ITERATOR_FIRST, (e) = set_iterate((s), &(i)); (e); (e) = set_iterate((s), &(i)))
-
-#define SET_FOREACH_BACKWARDS(e, s, i) \
-        for ((i) = ITERATOR_LAST, (e) = set_iterate_backwards((s), &(i)); (e); (e) = set_iterate_backwards((s), &(i)))
-
-#endif