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/e1_input.c b/openbsc/src/e1_input.c
index c894fe4..c20359c 100644
--- a/openbsc/src/e1_input.c
+++ b/openbsc/src/e1_input.c
@@ -40,18 +40,18 @@
 #define PF_ISDN AF_ISDN
 #endif
 
-#include <openbsc/select.h>
-#include <openbsc/msgb.h>
+#include <osmocore/select.h>
+#include <osmocore/msgb.h>
 #include <openbsc/debug.h>
 #include <openbsc/gsm_data.h>
 #include <openbsc/e1_input.h>
 #include <openbsc/abis_nm.h>
 #include <openbsc/abis_rsl.h>
-#include <openbsc/linuxlist.h>
+#include <osmocore/linuxlist.h>
 #include <openbsc/subchan_demux.h>
 #include <openbsc/trau_frame.h>
 #include <openbsc/trau_mux.h>
-#include <openbsc/talloc.h>
+#include <osmocore/talloc.h>
 #include <openbsc/signal.h>
 #include <openbsc/misdn.h>