Travis: also test on 32-bit Linux

diff --git a/RelNotes b/RelNotes
index bb52cf9476df53ddb9788f16082e2e92e76a4db5..7f250ddc2efa8f8d3a46ccecb4d810695387798a 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes/1.9.0.txt
\ No newline at end of file
+Documentation/RelNotes/2.11.1.txt
\ No newline at end of file