Rather than just discovering them by chance, a simple grep and some
search and replace are much more efficient! :-)
Cleaning only done on C and automake files.
Add a simple parser to the GimpSizeEntry widget so that one can write
things such as "40in" and "50%" in a size entry widget and get that
converted to the current unit.
The parser also handles basic expresions such as "20cm + 20px" and
"2 * 3.14in".
