[script.skinvariables] 2.1.14

[jurialmunkey]

Description

Add and update script.skinvariables for Nexus and higher.

Older version of the script exists on Matrix repo but I'm not updating against that version because some of the newer functionality only works for Nexus onwards.

NOTE
Requires script.module.jurialmunkey to be updated in repo first in this PR: #2624

Adds several skin helper tools (see wiki for details)
Adds XML template builders via advanced scripting rules
Adds node customisation tools for constructing skin XML layouts from a user config similar (more advanced skinshortcuts)
Adds plugin filters that allow for constructing widgets to merge plugin/library paths and apply advanced filtering
Lots more.

Checklist:

• My code follows the add-on rules and piracy stance of this project.
• I have read the CONTRIBUTING document
• Each add-on submission should be a single commit with using the following style: [script.foo.bar] 1.0.0

Additional information :

• Submitting your add-on to this specific branch makes it available to any Kodi version equal or higher than the branch name with the applicable Kodi dependencies limits.
• add-on development wiki page.
• Kodi pydocs provide information about the Python API
• PEP8 codingstyle which is considered best practise but not mandatory.
• This add-on repository has automated code guideline check which could help you improve your coding. You can find the results of these check at Codacy. You can create your own account as well to continuously monitor your python coding before submitting to repo.
• Development questions can be asked in the add-on development section on the Kodi forum.

[jurialmunkey]

Fixed the strings.po error the checker was complaining about. Obviously can't fix the dependency error as that is waiting on being merged too.