[TravisCI] show each command when setting up lua

.travis/setenv_lua.sh

@@ -1,3 +1,6 @@
+set -o xtrace
+set -e
+
 export PATH=${PATH}:$HOME/.lua:$HOME/.local/bin:$TRAVIS_BUILD_DIR/install/luarocks/bin
 bash .travis/setup_lua.sh
 eval `$HOME/.lua/luarocks path`

.travis/setup_lua.sh

@@ -6,6 +6,7 @@
 # luajit2.0 - master v2.0
 # luajit2.1 - master v2.1
 
+set -o xtrace
 set -eufo pipefail
 
 LUAJIT_VERSION="2.0.4"