Add Travis CI configuration (#359)

.travis.yml

@@ -0,0 +1,25 @@
+language: c
+install:
+  - |-
+    path="$(pwd)"; cd;
+    wget https://github.com/rednex/rgbds/archive/v0.2.5.tar.gz -O rgbds.tar.gz && 
+    tar xf rgbds.tar.gz && 
+    cd rgbds-0.2.5 && 
+    sudo make install && 
+    cd - && 
+    rm -rf rgbds && 
+    cd "$path"
+before_script:
+  - |-
+    function check_status() {
+      if ! git diff-index --quiet --ignore-submodules=all HEAD --; then
+        echo 'Uncommitted changes detected:';
+        git diff-index HEAD --;
+        return 1;
+      fi;
+    }
+script:
+  - make crystal crystal11
+  - make compare
+#  - check_status
+