fix conflicts and merge with master

diff --cc gtk2_ardour/ardour_ui.cc
Simple merge

diff --cc gtk2_ardour/utils.cc
Simple merge

diff --cc libs/ardour/ardour/session.h
Simple merge

diff --cc libs/ardour/session.cc
Simple merge

diff --cc libs/ardour/session_state.cc
Simple merge

diff --cc libs/surfaces/wscript
index 335d14ee87309949e9bcc56d6e394c8d5784f4d7,d9009bee253a1ad8e0b02051a8fb377406410099..29edc427b26628ef7094e2ed9debc8d66c8a7988
--- 1/libs/surfaces/wscript
--- 2/libs/surfaces/wscript
+++ b/libs/surfaces/wscript
@@@ -55,9 -53,11 +55,12 @@@ def configure(conf)
      if conf.is_defined('HAVE_CWIID_H'):
          conf.check_cc (header_name='bluetooth/bluetooth.h', define_name='HAVE_BLUETOOTH_H',mandatory=False)
          if conf.is_defined('HAVE_BLUETOOTH_H'):
-             autowaf.check_pkg(conf, 'cwiid', uselib_store='CWIID', atleast_version='0.6.00')
-             conf.define ('BUILD_WIIMOTE', 1)
-             sub_config_and_use(conf, 'wiimote')
+             autowaf.check_pkg(conf, 'cwiid', uselib_store='CWIID', atleast_version='0.6.00',mandatory=False)
+             if conf.is_defined ('HAVE_CWIID'):
+                 conf.define ('BUILD_WIIMOTE', 1)
++                sub_config_and_use(conf, 'wiimote')
+             else:
+                 print('You have the cwiid headers needed to compile wiimote support BUT you are missing the pkg-config file for cwiid')
          else:
              print('You are missing the libbluetooth headers needed to compile wiimote support')
      else: