split 'libosmocore' from openbsc codebase

This library is intended to collect all generic/common funcitionality
of all Osmocom.org projects, including OpenBSC but also OsmocomBB

The library currently includes the following modules:

bitvec, comp128, gsm_utils, msgb, select, signal, statistics, talloc, timer,
tlv_parse, linuxlist

msgb allocation error debugging had to be temporarily disabled as it depends on
'debug.c' functionality which at the moment remains in OpenBSC
diff --git a/openbsc/src/handover_logic.c b/openbsc/src/handover_logic.c
index 1bf048f..bd4c563 100644
--- a/openbsc/src/handover_logic.c
+++ b/openbsc/src/handover_logic.c
@@ -29,16 +29,16 @@
 #include <time.h>
 #include <netinet/in.h>
 
-#include <openbsc/msgb.h>
+#include <osmocore/msgb.h>
 #include <openbsc/debug.h>
 #include <openbsc/gsm_data.h>
-#include <openbsc/gsm_utils.h>
+#include <osmocore/gsm_utils.h>
 #include <openbsc/gsm_subscriber.h>
 #include <openbsc/gsm_04_08.h>
 #include <openbsc/abis_rsl.h>
 #include <openbsc/chan_alloc.h>
 #include <openbsc/signal.h>
-#include <openbsc/talloc.h>
+#include <osmocore/talloc.h>
 #include <openbsc/transaction.h>
 #include <openbsc/rtp_proxy.h>