C2-like search expression &cF+&lemma containing a '+' are incorrectly treated as a regex expression.

[Bodmo]

A lemma expression (in the C2 QL) like &cF+&Haus should be transformed like this:

{"@type":"koral:term","match":"match:eq","key":"cF+&Haus", "layer":"lemma"} , i.e.

layer=lemma and key = the whole search word with the options: 'cF+&Haus' (correct).

Instead, the '+' turns erroneously the key into a regex expr:

{"@type":"koral:term","match":"match:eq","type":"type:regex", "key":"cF.?&Haus","layer":"lemma"}