By using actual Unicode characters for the various ✔️ and ❌ marks
in the table, Doxygen will format it properly.
Also:
- Changed to superscripted numerals, for the various callouts
- Reformatted notes into a corresponding ordered list
- Added invisible spaces after the marks without a callout, to
balance centering
- Added center-alignment markers to appropriate table columns
Also include the documentation MarkDown pages in the Doxygen docs.
These will show up as Related Pages in the interface.
* The formatting of `INSTALL-*.md` had to be changed some:
- Doxygen doesn't support headings in bulleted lists (lines starting
with `* ###`) -- I'm not even sure that's legal markdown. They were
changed to just level 3 headings (lines starting with `###`).
- ALL Windows paths in `INSTALL-WINDOWS.md` were wrapped in backticks,
to prevent Doxygen parsing them as markup commands.
- Level 1 headings were added to the top of the three install docs,
giving them the title "Building libopenshot for ___(OS)___".
Otherwise all three pages were titled "Getting Started".
* Separately, the table at the top of `HW-ACCEL.md` does not
translate well to Doxygen. It will need further polishing. But the
docs are all quite readable now.
