`LF_STRUCTURE` parsing foiled by comma for templates

[disinvite]

If we are unlucky with the 255-character cutoff for a template type, the text will have two commas in a row, one for the template and one preceding the UDT number.

For example:

0x3faf : Length = 278, Leaf = 0x1505 LF_STRUCTURE
        # members = 0,  field list type 0x0000, FORWARD REF,
        Derivation list type 0x0000, VT shape type 0x0000
        Size = 0, class name = pair<_Tree<char const *,pair<char const * const,IsleTextureInfo *>,map<char const *,IsleTextureInfo *,IsleContainerInfoComparator,allocator<IsleTextureInfo *> >::_Kfn,IsleContainerInfoComparator,allocator<IsleTextureInfo *> >::iterator,_Tree<char const *,, UDT(0x000084b1)

Our regular expression doesn't parse this correctly.

Marking low priority because this has apparently not caused any issues for LEGO1.