Merge branch 'jolly_new'
Merge is based on jolly_new branch with two modifications.
1. Modified PCU L1 interface.
pcu_l1_if.cpp - common functions for tx and rx messages on L1 interface.
sysmo_sock.cpp - SYSMO-PCU socket functions.
openbts_sock.cpp - OpenBTS-PCU socket functions.
pcuif_proto.h - L1 interface's primitives.
2. Modified encoding of RLC/MAC Control messages, now we use structures and encode_gsm_rlcmac_downlink() function for encode control blocks (without  hand-coding).
diff --git a/configure.ac b/configure.ac
index 9fe9fdd..c572c88 100644
--- a/configure.ac
+++ b/configure.ac
@@ -24,7 +24,7 @@
 PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore  >= 0.3.9)
 PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty)
 PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm >= 0.3.3)
-PKG_CHECK_MODULES(LIBOSMOGB, libosmogb >= 0.5.2)
+PKG_CHECK_MODULES(LIBOSMOGB, libosmogb >= 0.5.1.4)
 
 AC_MSG_CHECKING([whether to enable sysmocom-bts hardware support])
 AC_ARG_ENABLE(sysmocom-bts,