cleaned up Serailization section of tutorial

Author: tclose

docs/source/tutorial/7-canonical-form.ipynb

@@ -242,7 +242,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Serialisation\n",
+    "## Serialization\n",
     "\n",
     "As well as the dataclass-like canonical form, it is also possible to represent all tasks\n",
     "in a nested dictionary form, which could be written to a static file (e.g. in JSON or\n",
@@ -290,9 +290,8 @@
    "metadata": {},
    "source": [
     "Noting that there is still a little more work has to be done to serialise some Python\n",
-    "objects, such as the `type` field and `xor` before it could be written to JSON/YAML. \n",
-    "This is more challenging for task definitions containing Python functions such as Python\n",
-    "and Workflow tasks or Shell tasks with converters, validators or callables, e.g."
+    "objects, e.g. classes used in field types and functions that are run in Python and\n",
+    "construct workflows in workflow tasks, before the serialized form can be written to JSON/YAML."
    ]
   },
   {