npm allows scopes to avoid name collisions. In order to support this
optional feature a flag has been added so that the name in the generated
package.json is correct.
Example for a package named wasm-add:
```bash
wasm-pack init
```
package.json
```json
{
"name": "wasm-add"
}
```
```bash
wasm-pack init --scope mgattozzi
```
package.json
```json
{
"name": "@mgattozzi/wasm-add"
}
```
Ashley Williams