EXPORT FILTER :

VERSION 1
	- border											DONE
	- multirow										DONE
	- column color								DONE
	- row color 									
	- nb col and row with column and row 
	- cell color									DONE
	- text font										
	- use params from the dialog	
	- inherit row and column 
		format for cell format. Make
		a Format(Format, Format) constructor.
VERSION 2
	- formula											
	- column format								
	- row format									

IMPORT FILTER :
	- lexical parser 							DONE
	- syntax. parser 							DONE
	- import filter in kspread