Update dependencies for elasticsearch 5

requirements.txt

@@ -15,9 +15,8 @@ cryptography==1.7.1
 dnspython==1.15.0
 docutils==0.14
 duo-client==3.0
-elasticsearch==2.4.0
-elasticsearch-dsl==2.1.0
-elasticutils==0.8.2
+elasticsearch>=5.0.0,<6.0.0
+elasticsearch-dsl>=5.0.0,<6.0.0
 enum34==1.1.6
 futures==3.1.1
 geoip2==2.5.0
@@ -43,7 +42,6 @@ packaging==16.8
 pyasn1==0.1.9
 pyasn1-modules==0.0.5
 pycparser==2.17
-pyelasticsearch==0.6.1
 pymongo==2.6.3
 pynsive==0.2.6
 pyOpenSSL==16.2.0