Feature request: tag_map equivalent for dependency relations

[danielhers]

The pos attribute is very useful for cross-lingual applications, as it has a universal set of values.
However, dep has different values for English (CLEAR) and German (TIGER) than other languages (UD). While I think a UD model for every language would be nice, in the meantime perhaps it would be easier to add a dep_map for English and German, and an attribute called something like udep providing the value of the mapped relation.

[honnibal]

This would make a good extension attribute, although it might be difficult to create a good mapping, since the labels won't align one-to-one.

[danielhers]

Right, the best mapping won't be 100%, but it should be pretty good nonetheless. For POS tags it's not one-to-one either, or is it?