Previously, I used a shell script to extract modification date ranges
from the Git history, but that was complicated and unreliable, so now
every file just gets the same year range in its copyright header. If
someone needs to know when a specific file was modified and by whom,
they can look at the Git history themselves; no need to include it
redundantly in the header.
Previously, Deflater.deflate would pass Z_SYNC_FLUSH to zlib
unconditionally, which caused the output to be enormous when setInput
was called repeatedly with very small input buffers. In order to
allow zlib to buffer output and thereby maximize compression, we must
use Z_NO_FLUSH until Deflater.finish is called, at which point we
switch to Z_FINISH. We also modify DeflaterOutputStream.close to call
Deflater.finish and write any remaining output to the wrapped stream.
