Skip step if "example" config file not found

[dsolovay]

This error should not occur if rerunning install step. It should gracefully skip, and log a WARN message.

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Sitecore Instance Manager
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Modules: installing archive-based modules action failed with message: Could not find file 'D:\websites\sc82u0aa\Website\App_Config\Include\Sitecore.ContentSearch.Solr.DefaultIndexConfiguration.config.example'.

You can find details in the log file. Would you like to open it?
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OK   Cancel   
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