Update django-countries to the latest supported version

docs/shared/requirements.txt

@@ -10,7 +10,7 @@ boto==2.6.0
 celery==3.0.19
 distribute>=0.6.28, <0.7
 django-celery==3.0.17
-django-countries==1.5
+django-countries==4.0
 django-filter==0.11.0
 django-mako==0.1.5pre
 django-mptt==0.5.5

openedx/core/djangoapps/user_api/tests/test_constants.py

@@ -145,7 +145,7 @@ SORTED_COUNTRIES = [
     (u"YT", u"Mayotte"),
     (u"MX", u"Mexico"),
     (u"FM", u"Micronesia (Federated States of)"),
-    (u"MD", u"Moldovia"),
+    (u"MD", u"Moldova"),
     (u"MC", u"Monaco"),
     (u"MN", u"Mongolia"),
     (u"ME", u"Montenegro"),
@@ -236,7 +236,7 @@ SORTED_COUNTRIES = [
     (u"UG", u"Uganda"),
     (u"UA", u"Ukraine"),
     (u"AE", u"United Arab Emirates"),
-    (u"GB", u"United Kingdom of Great Britain and Northern Ireland"),
+    (u"GB", u"United Kingdom"),
     (u"UM", u"United States Minor Outlying Islands"),
     (u"US", u"United States of America"),
     (u"UY", u"Uruguay"),

requirements/edx/base.txt

@@ -17,7 +17,7 @@ defusedxml==0.4.1
 django-babel-underscore==0.4.2
 django-celery==3.1.16
 django-config-models==0.1.3
-django-countries==3.3
+django-countries==4.0
 django-extensions==1.5.9
 django-filter==0.11.0
 django-ipware==1.1.0