Add configuration change, to prevent state loss

[wax911]

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Feature Information

Current the library will clear all search items when the device configuration is changed. It would be handy to have some sort of saved instance state when this happens so that the library retains state in such cases.

Solution Information

We could use override onSaveInstanceState and onRestoreInstanceState in our MutliSearch class, in addition to this we might need to introduce a data class to hold information about search terms and last selected index (this would be what we will put in bundles) which we would use to restore state from