feat: In mermaid blocks replace \n with <br/>

- Makes writing diagrams more convenient
- Matches how github flavored markdown handles mermaid blocks
- This was brought up in #140

otterwiki/renderer.py

@@ -148,6 +148,8 @@ def block_code(self, code, info=None):
             html = "".join(
                 ["\\[{}\\]".format(line) for line in code.strip().splitlines()]
             )
+            # replace \n with <br/> for convinient diagram writing (and match the github syntax)
+            code = code.replace("\\n","<br/>")
             return '\n<pre class="mermaid">{}</pre>\n'.format(
                 code.strip()
             )