Log Message:
x11/x3270: update to 4.3ga4

Some changes since 4.2ga10:

    Added support for minimum and maximum TLS protocol versions, via the
tlsMinProtocol resource, tlsMaxProtocol resource, -tlsminprotocol
command-line option and -tlsmaxprotocol command-line option.
    Added support for miscellaneous IND$FILE options via the
otherOptions keyword of the Transfer() action, the ftOtherOptions
resource, and extensions to the x3270 file transfer dialog and the c3270
interactive Transfer() action.
    Extended the cancel keyword of the Transfer() action so it will
interrupt the initial wait for an acknowledgement from the host IND$FILE
command.
    The Transfer() action now returns a summary on success or a
meaningful error message on failure.
    Added the Echo() action.
    Added support for the NEW-ENVRONMENT variables needed by the IBM
Express Logon Feature. (Feature request)

    When inserting in blank fill mode, trailing underscores are no
longer consumed, unless they are at the end of the field. (Bug report)