LOW / Add methods to access cells from a sheet:
- getCellValue(String column, String row) 
- setCellValue(String column, String row, String value) 
columns/rows are in a same notation as displayed in excel such as:
"AA" , "1"
- getCellFromNameValue(String name) 
- setCellFromNameValue(String name, String value) 
columns/rows are in a same notation as name in excel such as:
"AA1"