more robust error message (avoid undef)

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3628 2d0c7756-e317-0410-b71c-cbb6040a58f7
refactor script processing: to be careful about deciphering/denesting; this lets us recognize pairing of mid's so we can generate munderover; be careful about order so postsuperscript inside of midscripts remains; remove OVERUNDERHACKS which was the wrong way to do it, use phantoms to recenter mid scripts instead (very special case for primed sums)

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3629 2d0c7756-e317-0410-b71c-cbb6040a58f7
 memory leaks closed 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3630 2d0c7756-e317-0410-b71c-cbb6040a58f7
 purge away log handle 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3631 2d0c7756-e317-0410-b71c-cbb6040a58f7
 what seems to be a better memory leak test 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3632 2d0c7756-e317-0410-b71c-cbb6040a58f7
 check for LibXML version and report leaky if old 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3633 2d0c7756-e317-0410-b71c-cbb6040a58f7
 phasing out use of removeChildNodes 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3634 2d0c7756-e317-0410-b71c-cbb6040a58f7
 giving up on the classic workflow, just testing LaTeXML::Converter's memory 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3635 2d0c7756-e317-0410-b71c-cbb6040a58f7
 plan better 

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3636 2d0c7756-e317-0410-b71c-cbb6040a58f7
Merge latest changes and rebuild package

Change-Id: I1924a09219401cdd5e81f3a56136a2e82efaabe3
use cleaner DESTROY method to avoid global vars & memory leaks; Thanks Deyan

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3637 2d0c7756-e317-0410-b71c-cbb6040a58f7
weaken circular reference to avoid memory leaks; Thanks Deyan

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3638 2d0c7756-e317-0410-b71c-cbb6040a58f7
avoid LibXML method removeChildNodes as it apparently causes memory leaks; Thanks Deyan

git-svn-id: https://svn.mathweb.org/repos/LaTeXML@3639 2d0c7756-e317-0410-b71c-cbb6040a58f7
Merge remote-tracking branch 'git-svn' into upstream