Fix the remaining tests that failed with core.autocrlf=true

The test suite is mainly developed on Linux and MacOSX, which is the
reason that nobody thought to mark files as LF-only as needed.

The symptom is a test suite that fails left and right when being checked
out using Git for Windows (which defaults to core.autocrlf=true).

Mostly, the problems stem from Git's (LF-only) output being compared to
hard-coded files that are checked out with line endings according to
core.autocrlf (which is of course incorrect). This includes the two test
files in t/diff-lib/, README and COPYING.

This patch can be validated even on Linux by using this cadence:

	git config core.autocrlf true
	rm .git/index && git stash
	make -j15 DEVELOPER=1 test

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/.gitattributes

@@ -1,2 +1,21 @@
 t[0-9][0-9][0-9][0-9]/* -whitespace
-t0110/url-* binary
+/diff-lib/* eol=lf
+/t0110/url-* binary
+/t3900/*.txt eol=lf
+/t3901/*.txt eol=lf
+/t4034/*/* eol=lf
+/t4013/* eol=lf
+/t4018/* eol=lf
+/t4100/* eol=lf
+/t4101/* eol=lf
+/t4109/* eol=lf
+/t4110/* eol=lf
+/t4135/* eol=lf
+/t4211/* eol=lf
+/t4252/* eol=lf
+/t5100/* eol=lf
+/t5515/* eol=lf
+/t556x_common eol=lf
+/t7500/* eol=lf
+/t8005/*.txt eol=lf
+/t9*/*.dump eol=lf