Make Fileinfo more readable in HFilePrettyPrinter

Fileinfo:
    BLOOM_FILTER_TYPE = ROW
    DELETE_FAMILY_COUNT = \x00\x00\x00\x00\x00\x00\x00\x00
    EARLIEST_PUT_TS = \x00\x00\x01^Q\xF6\x0E\xCF
    KEY_VALUE_VERSION = \x00\x00\x00\x01
    LAST_BLOOM_KEY = f
    MAJOR_COMPACTION_KEY = \xFF
    MAX_MEMSTORE_TS_KEY = \x00\x00\x00\x00\x00\x00\x00\x18
    MAX_SEQ_ID_KEY = 27
    TIMERANGE = 1504613633743....1506570582061
    hfile.AVG_KEY_LEN = 14
    hfile.AVG_VALUE_LEN = 3
    hfile.CREATE_TIME_TS = \x00\x00\x01^\xC6\xB4J\xF9
    hfile.LASTKEY = \x00\x01f\x01i\x00\x00\x01^\xC6\x9A\xB8-\x04