Add docs

docs/salesforce.md

@@ -21,7 +21,6 @@ creates Snowfakery.
 The easiest way to learn about CumulusCI (and to learn how to
 install it) is with its [Trailhead Trail](https://trailhead.salesforce.com/en/content/learn/trails/build-applications-with-cumulusci).
 
-
 ```s
 $ cci task run generate_and_load_from_yaml -o generator_yaml examples/salesforce/Contact.recipe.yml -o num_records 300 -o num_records_tablename Contact --org qa
 ...
@@ -51,6 +50,11 @@ $ cci flow run test_everything
 ...
 ```
 
+The order in which sobjects is loaded is inferred by Snowfakery and CumulusCI
+based primarily on which tables have fields that depend on which other
+tables. Tables declared earlier in the recipe are also generally loaded
+before tables declared later.
+
 ## Incorporating Information from Salesforce
 
 There are various cases where it might be helpful to relate newly created synthetic
@@ -323,7 +327,8 @@ in the `PersonContactId` field.
 There is also an alternate syntax which allows nicknaming:
 
 ```yaml
-...
+
+---
 - object: Account
   fields:
     PersonContactId: