PhoneIsland: url-parameter refactor

[tonyco97]

Steps to reproduce

• Open phone-island inside an html template and try to receive a call

Expected behavior

You should be able to use url-parameter standalone without NethVoiceCTI app or NethLink

Actual behavior

Phone-island only send url-parameter event but it doesn't manage the opening page

Components

Phone-island latest version

[tonyco97]

Testing release: https://github.com/nethesis/ns8-nethvoice/releases/tag/1.4.3-testing.7