Swagger API: clean the API to alligned to 1.2

This patch clean the swagger definition file so it could be validated
with a 1.2 swagger validator.

The main changes are:
all types are declared as "type"
all modules have an "id" field

The only code change result from this patch is the result of renaming
path parameter "if" to "intf" as "if" was rejected as a reserve word.

Signed-off-by: Amnon Heiman <amnon@cloudius-systems.com>
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>