Move env section to the top of travis.yml

This makes the file easier to understand as a reader see where the
variable come from before they are used.

.travis.yml

@@ -1,3 +1,15 @@
+env:
+   global:
+      - secure: "HIj3p+p2PV8DBVg/KGUx6n83KwB0ASE5FwOn0SMB9zxnzAqe8sapwdBQdMdq0sXB7xT1spJqRxuxOMVEVn35BNLu7bxMLfa4287C8YXcomnvmv9xruxAsjsIewnNQ80vtPVbQddBPxa4jKbqgPby5QhhAP8KANAqYe44pIV70fY="
+      - GH_DOC_BRANCH: develop
+      - GH_REPOSITORY: github.com/MDAnalysis/mdanalysis.git
+      - GIT_CI_USER: TravisCI
+      - GIT_CI_EMAIL: [email protected]
+      - MDA_DOCDIR: package/doc/html
+   matrix:
+   - SETUP=full CYTHONIZE=true
+   - SETUP=full CYTHONIZE=false
+   - SETUP=minimal CYTHONIZE=false
 language: python
 python:
   - "2.7"
@@ -44,16 +56,3 @@ after_success:
      test ${TRAVIS_BRANCH} == ${GH_DOC_BRANCH} && \
      test "${TRAVIS_BUILD_NUMBER}.1" == "${TRAVIS_JOB_NUMBER}" && \
      bash ./maintainer/deploy_docs.sh
-
-env:
-   global:
-      - secure: "HIj3p+p2PV8DBVg/KGUx6n83KwB0ASE5FwOn0SMB9zxnzAqe8sapwdBQdMdq0sXB7xT1spJqRxuxOMVEVn35BNLu7bxMLfa4287C8YXcomnvmv9xruxAsjsIewnNQ80vtPVbQddBPxa4jKbqgPby5QhhAP8KANAqYe44pIV70fY="
-      - GH_DOC_BRANCH: develop
-      - GH_REPOSITORY: github.com/MDAnalysis/mdanalysis.git
-      - GIT_CI_USER: TravisCI
-      - GIT_CI_EMAIL: [email protected]
-      - MDA_DOCDIR: package/doc/html
-   matrix:
-   - SETUP=full CYTHONIZE=true
-   - SETUP=full CYTHONIZE=false
-   - SETUP=minimal CYTHONIZE=false