manual import via doit doesn't work for non-packages

Nobody has claimed this yet.

When evaluating an import statement such as `import { h } from "virtual-dom";` from a module that is not contained inside a lively package, the import will not resolve the module correctly, i.e. `h` in the example will be undefined.

Config code:

``` json
"systemjs": {
"map": {"virtual-dom": "./node_modules/virtual-dom/dist/virtual-dom.js"},
"meta": {"node_modules/virtual-dom/dist/virtual-dom.js": {"format": "amd"}}
}
```

It seems that the import statement doesn't use the parent module for lookup:
`await System.normalize("virtual-dom")` => `http://localhost:9001/virtual-dom`
vs.
`await System.normalize("virtual-dom", lively.modules.module("lively.morphic/index.js").id)` => `http://localhost:9001/node_modules/lively.morphic/node_modules/virtual-dom/dist/virtual-dom.js`

Start by reproducing the two System.normalize calls and the import from lively.morphic/index.js using the shown SystemJS map and meta configuration. Trace how the parent module is passed during lookup; done when the non-package import resolves the mapped virtual-dom module and h is defined.

Written by the indexing model from the issue text.