[BUG_FIX] add null checking
[REFACTORING] rename strategy
add new mining strategy
[BUG_FIX]
[MINOR_CHANGE] remove header of CSV file
make strategy controller capable for multiple strategies
update config file to have multiple strategies
add an interface to represent a mining strategy that write the results to files
remove a method to get date as a string
add a new class to have constnats related to configuration
add a method to get file name from pattern
extract ConfigXMLNode as a public class
add children nodes to xml node