* big pre-summer refactoring

+ introduce php7.4 and stay only php7.3 as max older version
+ workspace with php7.4 in future commits

docker-compose.elastic.yml

@@ -0,0 +1,24 @@
+version: '3.6'
+
+services:
+  elasticsearch752:
+    extends:
+      file: docker-compose.elasticsearch.base.yml
+      service: elasticsearch
+    build:
+      context: ./dockerfiles/elasticsearch752
+    volumes:
+      - elastic752:/usr/share/elasticsearch/data
+
+  elasticsearch732:
+    extends:
+      file: docker-compose.elasticsearch.base.yml
+      service: elasticsearch
+    build:
+      context: ./dockerfiles/elasticsearch732
+    volumes:
+      - elastic732:/usr/share/elasticsearch/data
+
+volumes:
+  elastic752:
+  elastic732: