Excluded pypy/Django 2.0 from Travis

Django 2.0 doesn't support Python 2.

Author: timgraham

.travis.yml

@@ -94,6 +94,12 @@ matrix:
           env: DJANGO_VERSION=">=2.1,<2.2" VERSION_ES=">=2.0.0,<3.0.0"
         - python: 3.4
           env: DJANGO_VERSION=">=2.1,<2.2" VERSION_ES=">=1.0.0,<2.0.0"
+        - python: pypy
+          env: DJANGO_VERSION=">=2.0,<2.1" VERSION_ES=">=5.0.0,<6.0.0"
+        - python: pypy
+          env: DJANGO_VERSION=">=2.0,<2.1" VERSION_ES=">=2.0.0,<3.0.0"
+        - python: pypy
+          env: DJANGO_VERSION=">=2.0,<2.1" VERSION_ES=">=1.0.0,<2.0.0"
         - python: pypy
           env: DJANGO_VERSION=">=2.1,<2.2" VERSION_ES=">=5.0.0,<6.0.0"
         - python: pypy