Match "DONE ()" as done for "all DONE" drivers

Before this "DONE ()" would incorrectly mark the extension as
done for all drivers instead of the drivers in the"all DONE"
driver list.

Signed-off-by: Tobias Droste <tdroste@gmx.de>
Match "DONE (0 binary formats)" as "DONE" for GL_ARB_get_program_binary

GL_ARB_get_program_binary has a hint in the parenthesis which
is not a list of dirvers that support the extension.
Mark all extensions as done for all drivers, if the hint
is not a list of drivers.

Signed-off-by: Tobias Droste <tdroste@gmx.de>
Mark everything that's not "DONE" or "not started" as "started"

There are multiple expressions to show that there is some progress
going on, but for the items that are DONE or not started the expression
is always the same. So mark everything as started that has an unknown
expression.

Signed-off-by: Tobias Droste <tdroste@gmx.de>
Show comments from GL3.txt as footnotes

Add comments regarding who is working on an item or
restrictions as footnotes at the bottom of the page.

Signed-off-by: Tobias Droste <tdroste@gmx.de>
Make line hovering more visible

Make the border of the currently highlighted line a little bit wider,
to make it more visible.

Signed-off-by: Tobias Droste <tdroste@gmx.de>