Fix the MJML template, and document our MJML template tag

cl8/templates/invite_new_profile.mjml.html

@@ -7,7 +7,7 @@
 <mj-body>
 <mj-section>
 <mj-column>
-<mj-text font-size="18px" line-height=1.5>
+<mj-text font-size="18px" line-height="1.5">
 <p>Dear {{ profile.name }},</p>
 <p>Welcome to {{ constellation }}.</p>
 <p>

cl8/templates/passwordless_default_token_email.mjml.html

@@ -7,7 +7,7 @@
 <mj-body>
 <mj-section>
 <mj-column>
-<mj-text font-size="18x" line-height=1.5>
+<mj-text font-size="18px" line-height="1.5">
 {% if user %}<p>Dear {{ user.profile.name }},</p>{% endif %}
 <p>
     <strong>{{ callback_token }}</strong> is your code to

cl8/users/templatetags/mjml.py

@@ -1,6 +1,13 @@
+import logging
+
 from django import template
 from mjml import mjml2html
 
+logger = logging.getLogger(__name__)
+# Used for convenience to see the contents of a template
+# before is passed as to convert from mjml to html for email
+# logger.setLevel(logging.DEBUG)  
+
 register = template.Library()
 
 
@@ -10,7 +17,6 @@ def __init__(self, nodelist):
 
     def render(self, context) -> str:
         mjml_source = self.nodelist.render(context)
-        breakpoint()
         return mjml_render(mjml_source)
 
 
@@ -35,4 +41,15 @@ def mjml(parser, token) -> MJMLRenderNode:
 
 
 def mjml_render(mjml_source: str) -> str:
+    """
+    Render the provided MJML template string, with template context
+    already added. Returns the html formatted for email clients.
+    """
+    logger.debug(mjml_source)
+
+    # Tip: mjml2html does not give very helpful error messages.
+    # Paste the `mjml_source` string into a validator like the one 
+    # below if is raising errors
+    # https://mjml.io/try-it-live/
+
     return mjml2html(mjml_source)