BUG: Fix documentation targets

Move 'doc' target to be created, initially with no dependencies, to the
root CMakeLists.txt, so that it is always available for non-Doxygen doc
targets (e.g. SlicerWizard-doc). Change doxygen doc target to be a
separate target that is then added as a dependency of 'doc' in the same
manner as SlicerWizard-doc. Remove logic to control when targets are
part of the default target except from the root 'doc' target (since
duplicating it is superfluous).

git-svn-id: http://svn.slicer.org/Slicer4/trunk@23004 3bd1e089-480b-0410-8dfb-8563597acbee
ENH: 1. A basic mode added with auto-examine (only scalar plugin)

2. Advanced option added (using other plugings)
3. Tables orientation is not dynamic. Default is vertical, horizontal can
be toggled by a checkbox
4. tables are now expandable

STYLE: changed the metadata viewer name

From: Alireza Mehrtash <mehrtash@bwh.harvard.edu>

git-svn-id: http://svn.slicer.org/Slicer4/trunk@23005 3bd1e089-480b-0410-8dfb-8563597acbee