Encode incoming url that addon receive from Kodi

[antonsoroko]

Description

Encode incoming url that addon receive from Kodi so then it can be used without errors to make request to elementum daemon.
example skin that sends "raw" strings to elementum: #1099
so in such case python part fails to make request because of spaces in url.

Related Issue

Motivation and Context

How Has This Been Tested?

if URL is already encoded (e.g. in "Search" elementum's menu entries are already encoded) - then nothing happens.
so the code looks safe, i believe.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Translation

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.