Minor tabulation and Doxygen comments fixes

From http://www.stack.nl/~dimitri/doxygen/manual/docblocks.html in "*Putting documentation after members*":
>If you want to document the members of a file, struct, union, class, or enum, it is sometimes desired to place the documentation block after the member instead of before. For this purpose you have to put an additional < marker in the comment block. Note that this also works for the parameters of a function.

This change should probably be propagated in the rest of the source code. :)