Detect delimiter in CSV rendering (#7869)

* detect csv delimiter in csv rendering

fixes #7868

* make linter happy

* fix failing testcase & use ints where possible

* expose markup type to template

previously all markup had the .markdown class, which is incorrect,
as it applies markdown CSS & JS logic to CSV rendering

* fix build (missing `make css`)

* ignore quoted csv content for delimiter scoring

also fix html generation

public/less/_repository.less

@@ -400,6 +400,10 @@
                 }
             }
 
+            .csv {
+                overflow-x: auto;
+            }
+
             pre {
                 overflow: auto;
             }