CHANGES SINCE 0.2-2

* interpTs: Fill with long-term mean or median.
* phenoPhase: Fixed problem where max.time month number given relative
	to subset rather than whole year
* plotSeas: Allow choice of number of intervals.
* plotTsTile: More informative error message when not enough data.
* seaRoll: Now allows frequencies other than 12.
* tsMake: Remove need to specify layer if no depth info.
* WqData plot method: Limit to specific fields (first 10 is default).
* WqData subset method: Removed because of strategy that WqData objects
	should not be changed, only created or destroyed.
* wqData: Argument value "narrow" changed to "long". 
* wqData: Now requires time.format to be specified.
* wqData: Now ensures variable is a factor when type = "long".
