Add Travis CI and LuaCheck

.luacheckrc

@@ -0,0 +1,15 @@
+unused_args = false
+allow_defined_top = true
+max_line_length = 999
+
+globals = {
+    "minercantile",
+}
+
+read_globals = {
+    string = {fields = {"split", "trim"}},
+    table = {fields = {"copy", "getn"}},
+
+    "minetest", "ItemStack",
+    "default", "unified_inventory",
+}

.travis.yml

@@ -0,0 +1,11 @@
+language: generic
+addons:
+  apt:
+    packages:
+    - luarocks
+before_install:
+  - luarocks install --local luacheck
+script:
+- $HOME/.luarocks/bin/luacheck .
+notifications:
+  email: false