Fix incorrect grouping symbols for Doxygen
Following https://www.doxygen.nl/manual/grouping.html one way to mark groups is by
///@{
...
///@}
Not, however,
//@{
...
//@}
The MR replaces occurences of the latter by the formed and adds a missing @name
to the description of the toVector()
and fromVector()
group. Fixes one sub-issue of #256.