[Taxacom] Interactive key update

[Timothy M. Jones]

New additions to Carex Interactive Key -

Added an "AVOID" character state to certain characters.
It is a "neutral" character that allows a user to skip a character.
This character was added to remove a character from the "best character" 
list.  If required, the character can easily be unchecked and used in 
the same determination.
 It is present in "*country, state and floristic zone*" and in "*Carex 
section*". 

Added histograms to certain characters and states to allow the user to 
visualize the data within the data matrix.  
Error and absence data  are not represented (for clarity). 
All histograms can be easily seen by expanding the features tree. 



Key at  http://utc.usu.edu/keys/Carex/Carex.html

Any input is greatly appreciated,
Tim