Locator plugins

[ortoniKC]

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Description

Motivation and Context

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)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[corevo]

Duplicate of #228
There is a reason I didn't accept my own PR, it's because I couldn't figure a way to record new locators through plugins, only to play them back.

You are more than welcome to fix my PR, and add that, if you find a way to do it, but as long as this PR is the exact same as #228 I will have to close it.