I now have enough of the driver working to be useful.
Read / write memories, a number of the settings, and import from RepeaterBook work.
Saving modes dn,vw and AMS in memory channels, do not currently work.
Banks have not been tested - may now work, VFO settings not implemented (etc)

I have also raised a request for C4FM to be added to CHIRP Modes. 

Feedback appreciated. Thanks.

nicolass-Mac-mini:tests nicolas$ python run_tests.py -d Yaesu_FT-70D

    Yaesu FT-70D        Detect      PASSED: All tests

    Yaesu FT-70D        Settings    PASSED: All tests

    Yaesu FT-70D        Clone       PASSED: All tests

    Yaesu FT-70D        Edges       PASSED: All tests

    Yaesu FT-70D        BruteForce  PASSED: All tests

    Yaesu FT-70D        CopyAll     PASSED: All tests

    Yaesu FT-70D        Banks       PASSED: All tests

----------------------------------------------------------------------

Results:

  TOTAL  : 7

  FAILED : 0

  SKIPPED: 0

  PASSED : 7

  CRASHED: 0

nicolass-Mac-mini:tests nicolas$