Merge branch 'ew/git-svn-http-tests'

Tests for "git svn" have been taught to reuse the lib-httpd test
infrastructure when testing the subversion integration that
interacts with subversion repositories served over the http://
protocol.

* ew/git-svn-http-tests:
git svn: migrate tests to use lib-httpd
t/t91*: do not say how to avoid the tests

diff --cc t/lib-git-svn.sh
Simple merge

diff --cc t/lib-httpd.sh
Simple merge

diff --cc t/lib-httpd/apache.conf
Simple merge

diff --cc t/t9100-git-svn-basic.sh
Simple merge

diff --cc t/t9120-git-svn-clone-with-percent-escapes.sh
Simple merge