Before this commit, the default font chosen for TTF text is Arial
(chosen by the basename of arial.ttf), which isn't present on most
Linux systems, and cannot be redistributed. After this commit, it is
replaced with Bitstream Vera Sans, which can be. Existing files
are not affected.
The font name in the TTF file was artificially modified to add
the (built-in) suffix, which will need to be done if more built-in
fonts are added.
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