1/28/2015 Changed require(ttr) to require(TTR) in various \donttest{} sections
1/28/2015 Added function allpairs.egcm
1/28/2015 Updated DESCRIPTION to include authors@R
1/28/2015 Default unit root test set to "pp"
11/12/2015 Updated to be compatible with newest release of ggplot
3/26/2016 Change the Dickey-Fuller, Phillips-Perron and PGFF unit root tests so 
          that they do not include a linear trend.
4/16/2016 Inserted exception handling for ca.jo(), which will fail when the two
          series are co-linear or nearly co-linear.
9/17/2017 Updated yegcm so that it fetches Yahoo data via quantmod rather
          than through TTR (thanks, Jonas Rende)
9/17/2017 Updated hurst exponent unit-root test so that it uses pracma::hurstexp
          rather than the now defunc fArma::aggvarfit