Remove some deprecated functions from l3str

As this is in l3experimental rather than l3kernel, simply removing the
old functions should be OK.


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4451 de43f980-851b-0410-b2f7-c40aca1f87e0
Move TOC in l3str

This will need to get revised again for a move to l3kernel


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4452 de43f980-851b-0410-b2f7-c40aca1f87e0