Removing older platform versions no longer supported for testing

Author: Johan Brichau

.travis.yml

@@ -4,10 +4,8 @@ smalltalk:
   - Pharo-5.0
   - Pharo-4.0
   - Pharo-3.0
-  - Pharo-2.0
-  - Squeak-4.4
   - Squeak-4.5
   - Squeak-5.0
-  - GemStone-2.4.4.1
   - GemStone-3.1.0.6
-  - GemStone-3.2.10
+  - GemStone-3.2.12
+  - GemStone-3.3.0