Instant Translate will find no en-us terms

Instant Translate will not use en-us terms from term collection when translating

• de to en (no sub language selected, but enabled)
• de to en (sublanguages disabled)

only en-gb terms are used unless en-us is explicitly selected (with enabled sublanguages)

this should be changed:
enabled sublanguages:

• de- to en should return gb and us
• de to en-gb should return en-gb only
• de to en-us should return en-us only

disabled sublanguages:

• de to en should return gb and us