upgrade to ES7

Author: Tamas Nyiri

.travis.yml

@@ -43,7 +43,7 @@ before_install:
 
 install:
   - "travis_retry pip install -r requirements.txt"
-  - "travis_retry pip install -e .[all,elasticsearch2]"
+  - "travis_retry pip install -e .[all]"
 
 script:
   - "./run-tests.sh"

setup.py

@@ -72,7 +72,7 @@
 
 INSTALL_REQUIRES = [
     'autosemver~=0.2,>=0.2',
-    'elasticsearch-dsl~=5.0',
+    'elasticsearch-dsl~=7.0',
     'Flask-BabelEx>=0.9.2',
     'invenio-access~=1.0,>=1.0.1',
     'invenio-search>=1.0.0a5',