fix formatting for datetime nested bullet points in docs/usage/types.md (#887)

docs/usage/types.md

@@ -190,37 +190,37 @@ types:
 
 * `datetime` fields can be:
 
-  * `datetime`, existing `datetime` object
-  * `int` or `float`, assumed as Unix time, i.e. seconds (if <= `2e10`) or milliseconds (if > `2e10`) since 1 January 1970
-  * `str`, following formats work:
+    * `datetime`, existing `datetime` object
+    * `int` or `float`, assumed as Unix time, i.e. seconds (if <= `2e10`) or milliseconds (if > `2e10`) since 1 January 1970
+    * `str`, following formats work:
 
-    * `YYYY-MM-DD[T]HH:MM[:SS[.ffffff]][Z[±]HH[:]MM]]]`
-    * `int` or `float` as a string (assumed as Unix time)
+        * `YYYY-MM-DD[T]HH:MM[:SS[.ffffff]][Z[±]HH[:]MM]]]`
+        * `int` or `float` as a string (assumed as Unix time)
 
 * `date` fields can be:
 
-  * `date`, existing `date` object
-  * `int` or `float`, see `datetime`
-  * `str`, following formats work:
-
-    * `YYYY-MM-DD`
+    * `date`, existing `date` object
     * `int` or `float`, see `datetime`
+    * `str`, following formats work:
+
+        * `YYYY-MM-DD`
+        * `int` or `float`, see `datetime`
 
 * `time` fields can be:
 
-  * `time`, existing `time` object
-  * `str`, following formats work:
+    * `time`, existing `time` object
+    * `str`, following formats work:
 
-    * `HH:MM[:SS[.ffffff]]`
+        * `HH:MM[:SS[.ffffff]]`
 
 * `timedelta` fields can be:
 
-  * `timedelta`, existing `timedelta` object
-  * `int` or `float`, assumed as seconds
-  * `str`, following formats work:
+    * `timedelta`, existing `timedelta` object
+    * `int` or `float`, assumed as seconds
+    * `str`, following formats work:
 
-    * `[-][DD ][HH:MM]SS[.ffffff]`
-    * `[±]P[DD]DT[HH]H[MM]M[SS]S` (ISO 8601 format for timedelta)
+        * `[-][DD ][HH:MM]SS[.ffffff]`
+        * `[±]P[DD]DT[HH]H[MM]M[SS]S` (ISO 8601 format for timedelta)
 
 ```py
 {!./examples/datetime_example.py!}