Remove pygobject in requirements as travis can't find dependency

.travis.yml

@@ -4,10 +4,9 @@ language: python
 
 python:
   - "3.4"
-  - "pypy"
 
 # command to install dependencies, e.g. pip install -r requirements.txt --use-mirrors
-install: pip install --allow-all-external -r requirements.txt
+install: pip install -r requirements.txt --use-mirrors
 
 # command to run tests, e.g. python setup.py test
 script: python setup.py test

requirements.txt

-wheel==0.24.0
-pygobject>=3
\ No newline at end of file
+wheel==0.24.0
\ No newline at end of file