Ensures that all files that Git considers to be text will have
normalized (LF) line endings in the repository. When core.eol is set to
native (which is the default), Git will convert the line endings of
normalized files in your working directory back to your platform's
native line ending.
See also https://git-scm.com/docs/gitattributes
This way, building the minsrc tarball doesn't require multiple versions
of Automake to be installed. (Most things were at the 1.11 version, but
some were at the 1.14 version.)
Building minsrc should now work just fine.
