Change log:

Version 0.1.1, Nov 18, 2020
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Bug fix such that Aggregate works when the table only contains numerics or dates. 
Bug fix with the 'by' parameter.

Version 0.1.0, Nov 17, 2020
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Re-written the code in data.table for computational speed. 
Added efficient dummy-coding also written in data.table.
Allowed the functionality to output a tibble. 

Version 0.0.2, Nov 20, 2015
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Added the functionality to compute recency and duration of Date variables by an ID

Version 0.0.1, Sep 30, 2015
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Submitted package to cran with one function: Aggregate
