Test against latest 4 google/cloud releases (#71)

* bash style guide and simpler before/after install hooks

* Allow Travis CI failures for PHP nightly and don't wait for them to complete

* Test Matrix of GCP SDK Versions

Arguments:
   packages                        Required package name optionally including a version constraint, e.g. foo/bar or foo/bar:1.0.0 or foo/bar=1.0.0 or "foo/bar 1.0.0"

* Don't prefer source or suggest stuff

* ✨ Test _all_ the versions ✨

* Maybe ordering is the problem

* Test less versions

* added additional packages to test against, ( dev master and the latest 3 versions.)

* testing logic.

* testing travis configuration

* escaping?

* moving.

* test again.

* testing against new versions

* added an additional logging row.

* testing against latest 3 packages

* see if we can retry here.

.travis.yml

@@ -11,23 +11,27 @@ php:
 
 env:
   - GOOGLE_CLOUD="0.21.*"
-  - GOOGLE_CLOUD="0.47.*"
-  - GOOGLE_CLOUD="0.48.*"
-  - GOOGLE_CLOUD="0.49.*"
+  - GOOGLE_CLOUD="0.43.*"
+  - RELEASE_TAG=1 # dev-master
+  - RELEASE_TAG=2 # latest-stable
+  - RELEASE_TAG=3 # previous-stable
 
 matrix:
   fast_finish: true
   allow_failures:
     - php: nightly
+    - env: RELEASE_TAG=1
 
 before_install:
   - bash -c 'if [[ "${TRAVIS_PHP_VERSION}" == "hhvm" ]]; then rm phpunit.xml; mv phpunit.hhvm.xml phpunit.xml; fi;'
 
 install:
+  - if [[ -z "$GOOGLE_CLOUD"  ]]; then GOOGLE_CLOUD=$(travis_retry composer show google/cloud -a | grep versions | cut -d "," -f ${RELEASE_TAG} |  sed -e "s/^versions ://" | xargs); fi;
   - travis_retry composer require --no-interaction --no-suggest "google/cloud:${GOOGLE_CLOUD}"
   - travis_retry composer install --no-interaction --no-suggest
 
 script:
+  - export GOOGLE_CLOUD=$GOOGLE_CLOUD
   - bin/phpunit
 
 after_script: