Add properties to project.json

parent #235 

Default value of `requireLicenseAcceptance` is `false`. (I guess that's the most common case)

The value of `tags` can only be an array
```json
{
  "tags": ["tag1", "tag2", "tag3"]
}
```
Do we want to support other alternatives like string with separators?
```json
{
  "tags": "tag1, tag2, tag3"
}
```