Version 0.2.1
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  * Examples not run to ensure build completes on Mac OS
  * Move ggplot2 from dependency to suggest
  * Documentation updates
  * Minor bug fixes

Version 0.2.0
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  * Now handles errors from summaryRprof() more gracefully
  * Introduce replication argument for profiling of slowly-running 
    functions
  * microbenchmark now used to infer a good number of replications
    in each timeit call
