Merge branch 'stable-1.2'

# Conflicts:
#	.travis/linux..before_install.sh
#	.travis/linux..install.sh
#	cmake/linux/lmms.desktop
#	plugins/vst_base/CMakeLists.txt

.travis/linux..script.sh

@@ -1,4 +1,8 @@
 #!/usr/bin/env bash
+if [ $QT5 ]; then
+	unset QTDIR QT_PLUGIN_PATH LD_LIBRARY_PATH
+	source /opt/qt58/bin/qt58-env.sh
+fi
 
 set -e