updated dependency list
now the test cases will return a number of failing tests, making it possible to chain them and evaluate if the whole suite passed or not
for loop to run the binaries of the test cases
started a test case for the database handler unit
added an insertion function (without a write concern)
test cases now return the number of failing tests as a return value of main
dbh_insert now returns the result of mongo_insert; renamed one parameter in dbh_get_double
added dbh_get_string, updated dbh_get_double and added dbh_search_by_string functions
new tests for the added dbh functions
added tests for sample_std_dev function