Added version-dependent parsing for md5status (#9)
Added version-dependent parsing for md5status (#9)

* Added version-dependent parsing for md5status

Added LooseVersion import for version string comparison.
Added private attribute _atdver to store exact ATD software version upon connection.
Added conditional parsing of _md5log output depending on ATD version:
 - for ATD 3.8.0 and above use 'confidence' key when getting severity value from MD5 results log,
 - for ATD version < 3.8.0 use 'severity' key.

* Added type enforcement for integer return values

ATD REST API in version 3.8.0 does not consistently return int values as typed int. Sometimes they are string representations.

* deduplicate int() call

passimens/atdlib