#248 flag-is-epsilon is not implemented in hfst-xfst

[sjurum]

hfst[0]: show variables
[...]
           directory:   OFF: <NOT IMPLEMENTED>
      encode-weights:   OFF: encode weights when minimizing
     flag-is-epsilon:   OFF: <NOT IMPLEMENTED>

The lack of this feature makes it very hard to handle certain upper- and lower-casing processes in a way that is source-code compatible with the Xerox tools. An implementation of it would be very welcome :)

Tested with:

$ hfst-info 
No tests selected; printing known data
HFST info version: 0.1
HFST packaging: hfst 3.7.1
HFST version: 3.7.1
HFST long version: 300070001
HFST configuration revision: $Revision: 3900 $
OpenFst supported
SFST supported
Unicode support: no (hfst)

[Erik Axelson]

Implemented.