Fixes for three l3trial modules after l3seq changes.


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4573 de43f980-851b-0410-b2f7-c40aca1f87e0
A change of formatting \texttt => \meta

As the various branches are in the syntax section, use the correct syntax-
related markup.


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4574 de43f980-851b-0410-b2f7-c40aca1f87e0
Update bigint code to new approach to case tests


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4575 de43f980-851b-0410-b2f7-c40aca1f87e0