Don't test against master, not supported

Add tests against 3.2 instead, and remove 3.0 since it's no longer supported.

.travis.yml

@@ -5,9 +5,8 @@ php:
  - 5.3
 
 env:
- - DB=MYSQL CORE_RELEASE=3.0
  - DB=MYSQL CORE_RELEASE=3.1
- - DB=PGSQL CORE_RELEASE=master
+ - DB=MYSQL CORE_RELEASE=3.2
 
 before_script:
  - git clone git://github.com/silverstripe-labs/silverstripe-travis-support.git ~/travis-support
@@ -15,4 +14,4 @@ before_script:
  - cd ~/builds/ss
 
 script: 
- - phpunit textextraction/tests/
+ - phpunit textextraction/tests/