Build rel/ branches on Travis and AppVeyor.

.travis.yml

@@ -16,6 +16,7 @@ branches:
     - release
     - dev
     - /^(.*\/)?ci-.*$/
+    - /^rel\/.*/
 before_install:
   - if test "$TRAVIS_OS_NAME" == "osx"; then brew update; brew install openssl; ln -s /usr/local/opt/openssl/lib/libcrypto.1.0.0.dylib /usr/local/lib/; ln -s /usr/local/opt/openssl/lib/libssl.1.0.0.dylib /usr/local/lib/; fi
 script:

appveyor.yml

@@ -6,6 +6,7 @@ branches:
     - release
     - dev
     - /^(.*\/)?ci-.*$/
+    - /^rel\/.*/
 build_script:
   - ps: .\build.ps1
 clone_depth: 1