Merge branch 'jn/mime-type-with-params' into maint

* jn/mime-type-with-params:
gitweb: Serve */*+xml 'blob_plain' as text/plain with $prevent_xss
gitweb: Serve text/* 'blob_plain' as text/plain with $prevent_xss

diff --cc gitweb/gitweb.perl
Simple merge