Liquescent doesn't lose its `liquescent` tag when toggled in a ligature

[JoyfulGen]

If I have, say, a punctum and a liquescent and I want to make a ligature out of them, Neon does give me the option to toggle the neume components. But then the MEI looks likes this:

<neume xml:id="n126d7w2">
    <nc xml:id="ng0xyok" facs="#z1dq1ez0" oct="3" pname="b" ligated="true"/>
    <nc xml:id="n1uyblwn" facs="#z9v6ye7" oct="3" pname="a" ligated="true">
        <liquescent xml:id="ljwqlsm"/>
    </nc>
</neume>

The nc's are ligated, but the liquescent tag is still there! It looks even weirder if the liquescent is the first neume component instead of the second:

<neume xml:id="n1hwmoal">
    <nc xml:id="n1vztub6" facs="#z1fkqwnd" oct="3" pname="b" ligated="true">
       <liquescent xml:id="l173t2wj"/>
    </nc>
    <nc xml:id="np3hgzs" facs="#z4tkrg2" oct="3" pname="a" ligated="true"/>
</neume>

In Neon, it looks like this:

Ligature.with.liquescent.mov

I quite like that it's possible to make a ligature out of any neume shape, including liquescents. Can we keep that? Unless @annamorphism you think it's too weird?

[JoyfulGen]

All fixed, thank you! Closing issue now.