replace imports of q with bluebird

update `package.json`

```
find src test -name '*.js' |
    xargs perl -i -pe 'if (/require\(.[qQ].\)/) { $_ = "import Promise from '\''bluebird'\'';\n"; }'

find src test -name '*.js' |
    xargs perl -i -pe 'if (/import [qQ] /) { $_ = "import Promise from '\''bluebird'\'';\n"; }'
```

test/test-utils.js

@@ -1,6 +1,6 @@
 "use strict";
 
-var q = require('q');
+import Promise from 'bluebird';
 
 /**
  * Perform common actions before each test case, e.g. printing the test case