Given a list of strings, it returns a generic data type for the database
column that could best contain them: INTEGER, DOUBLE, STRING
If the strings passes a parseInteger: type = INTEGER if the strings
contain digits, 'E' (for exponential), dot, plus, minus: type = DOUBLE If
the strings contain letters or other characters: type = STRING Note: If
the string contains only digits, but also intervening white spaces: type
= STRING
Returns a date-time-milliseconds-nanoseconds stamp in the format:
20070117_111847_123_3000 yyyymmdd_hhmmss_lll_nnnn (the n digits are not
the nanoseconds! just a progressive stamp)