Add MD030 with tests, refactor list handling with flattenLists.

test/spaces_after_list_marker.md

@@ -0,0 +1,74 @@
+Normal list
+
+* Foo
+* Bar
+* Baz
+
+List with incorrect spacing
+
+*  Foo {MD030}
+*  Bar {MD030}
+*   Baz {MD030}
+
+List with children:
+
+* Foo {MD030}
+    * Bar {MD030}
+        * Baz
+
+List with children and correct spacing:
+
+*   Foo
+    *   Bar
+        * Baz (This sublist has no children)
+
+List with Multiple paragraphs and correct spacing
+
+*   Foo
+
+    Here is the second paragraph
+
+*   All items in the list need the same indent
+
+List with multiple paragraphs and incorrect spacing
+
+*  Foo {MD030}
+
+   Here is the second paragraph
+
+*    Bar {MD030}
+
+List with code blocks:
+
+*   Foo
+
+        Here is some code
+
+*   Bar
+
+Ordered lists:
+
+1. Foo
+1. Bar
+1. Baz
+
+And with incorrect spacing:
+
+1.  Foo {MD030}
+1.  Bar {MD030}
+1.  Baz {MD030}
+
+Ordered lists with children:
+
+1. Foo {MD030}
+    * Hi
+1. Bar {MD030}
+1. Baz {MD030}
+
+Ordered lists with children (correct spacing), and with something other than
+the first item determining that the entire list has children:
+
+1.  Foo
+1.  Bar
+    * Hi
+1.  Baz