Allow to use different API source (Lomadee)

The base URL was:

```
[env].buscape.com/service/[method]/[app_id]/?[parameter]=[value]
```

Now it is:

```
[env].buscape.com/service/[method]/[api]/[app_id]/?[parameter]=[value]
```

The api parameter is optional.
Small refactoring
fixing the gems source (use of https)
trully using the api in json format (for default)
merge with remote