HaikuBook: add remaining layout class documentation

This is the final contribution to #15368

* Tried to share more documentation in the various BLayoutBuilder classes
* Add missing GridView, GroupView, SpaceLayoutItem
* Also added AbstractLayoutItem, but hide the actual documentation behind
an `INTERNAL` conditional block. This block identifier can be used to
document parts of the API, to then hide them during a regular Doxygen run.
* Do some cleanup on other layout classes; add missing members, etc.
* The actual generated BLayoutBuilder::* html is a mess. I should investigate
this at a later time. Especially the copied members seem to mix type
definitions with member documentation. It is odd. Not unlikely to be a
Doxygen bug.
* The general documentation for the layout system could use an overhaul as
well, but this is for later.

Change-Id: I6db9ef105b4ae6de0f1ebb917f86f8b1c0d4ea2e
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2491
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

docs/user: Remove duplicate "ingroup interface" from layout docs.

Since the "Layout" group is a member of the "Interface" group,
Doxygen automatically adds the "Interface" group to all pages
in the "Layout" group, meaning that having an explicit "ingroup Interface"
created duplicate group tags.

IK documentation update

* Add \since directive to each method.
* Add documentation for BScrollBar and BScrollView classes.
* Title Case group titles.
* Some other minor documentation updates.

Remove enum elaborated type specifier

...from orientation params. Elaborated type specifiers are not needed
for C++ code and removing them makes doxygen happy. Verified working
on both gcc2h and gcc4h builds.

Big docs cleanup.

* Fixed headers including:
- All rights reserved not All Rights Reserved.
- name, email@domain.com not name <email@domain.com>
- tabs and spaces
- Authors: not Documented by:
* Renamed string.dox to String.dox
* Renamed midixxx.dox files to MidiXxx.dox
* Moved images into images subdirectories and updated Doxfile.
* Re-format all files with tabs instead of spaces.
* Fix many spelling mistakes.
* Added all files, classes, structs, and enums to libbe group.

Add \brief tag so description appears in files table

Merge work by John Scipione on the Haiku Book.
* Some new classes documented
* Screenshots for the interface kit controls
* A lot of typo fixes
* Some css tweaks

This has some backporting to the current version of Doxygen, since
there are experiments to get coloring similar to the one in the Be
Book that will hopefully be upstreamed in Doxygen.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42608 a95241bf-73f2-0310-859d-f6bbb57e9c96

Add initial documentation for Layout API, not everything is documented, and it's not perfect, but its time to commit this.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39055 a95241bf-73f2-0310-859d-f6bbb57e9c96

IK documentation update

* Add \since directive to each method.
* Add documentation for BScrollBar and BScrollView classes.
* Title Case group titles.
* Some other minor documentation updates.

Remove enum elaborated type specifier

...from orientation params. Elaborated type specifiers are not needed
for C++ code and removing them makes doxygen happy. Verified working
on both gcc2h and gcc4h builds.

Big docs cleanup.

* Fixed headers including:
- All rights reserved not All Rights Reserved.
- name, email@domain.com not name <email@domain.com>
- tabs and spaces
- Authors: not Documented by:
* Renamed string.dox to String.dox
* Renamed midixxx.dox files to MidiXxx.dox
* Moved images into images subdirectories and updated Doxfile.
* Re-format all files with tabs instead of spaces.
* Fix many spelling mistakes.
* Added all files, classes, structs, and enums to libbe group.

Add \brief tag so description appears in files table

Merge work by John Scipione on the Haiku Book.
* Some new classes documented
* Screenshots for the interface kit controls
* A lot of typo fixes
* Some css tweaks

This has some backporting to the current version of Doxygen, since
there are experiments to get coloring similar to the one in the Be
Book that will hopefully be upstreamed in Doxygen.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42608 a95241bf-73f2-0310-859d-f6bbb57e9c96

Add initial documentation for Layout API, not everything is documented, and it's not perfect, but its time to commit this.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39055 a95241bf-73f2-0310-859d-f6bbb57e9c96