Sort the names of plugins in the documentation. Upon visual inspection, also fix a number of formulas and text issues found in the manual's description of the various plugins.
Update, using the latest deal.II version.
log number of inner iterations in Stokes preconditioner
update test outputs
Sort the names of plugins.

Sort the names of plugins in the documentation. Upon visual inspection, also fix a number of formulas and text issues found in the manual's description of the various plugins.
Merge from upstream.