[Run][Plugin manager] Show error state on missing plugin requirements

[htcfreek]

Description

In plugin managers' spec we defined that plugins should show the error state.

I think a required tool (here everything) which missing is such a plugin error too.

Problem: The case plugin can't work because of missing requirements isn't covered by plugin manager at the moment.

Possible implementation

Suggestion 1

Dependency settings file, which is checked by pm and includes all program files/processes which are needed.

{
"requiredRunningProcesses" : ["everything.exe"],
"requiredExistingApps" : ["C:\\program files\\...\\everithing.exe"]
}

Suggestion 2

The plugin itself checks for dependencies and writes an ErrorState.json which is interpret by pm.

{
"errorState" : true,
"message" : "Something failed!",
"disablePlugin" : true
}

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cc: @mykhailopylyp , @crutkas , @enricogior

Originally posted by @htcfreek in #10937 (comment)