default branch defined for codecov.io (#5586)

* default branch defined for codecov.io

* improvements codecov
- disable comments
- enable checks

* removed mods from codecov statistic

.codecov.yml

@@ -0,0 +1,36 @@
+codecov:
+  branch: develop
+
+comment: off
+
+coverage:
+  status:
+    patch:
+      default: off
+      source:
+        target: 80%
+        flags: source
+      backend:
+        target: 80%
+        flags: backend
+    project:
+      default: off
+      source:
+        flags: source
+      backend:
+        flags: backend
+
+flags:
+  source:
+    paths:
+      - src/
+  backend:
+    paths:
+      - mod/
+      - include/
+  binary:
+    paths:
+      - bin/
+  tests:
+    paths:
+      - tests/