add travis (#8)

* check bash script with shellcheck and travis

* only check scripts in root directory

.travis.yml

@@ -0,0 +1,17 @@
+language: bash
+
+# Use container-based infrastructure for quicker build start-up
+sudo: false
+
+addons:
+  apt:
+    sources:
+    - debian-sid    # Grab shellcheck from the Debian repo (o_O)
+    packages:
+    - shellcheck
+
+script:
+ - 'shellcheck *.sh'
+
+matrix:
+  fast_finish: true