Remove empty documents (#1801)

These documents were part of a proposed structure. In the meantime, the
structure has diverged from the proposal. We also have issue #845 to
discuss a structure if we find time in the future to work on this.

Author: srittau

docs/index.rst

@@ -2,14 +2,6 @@
 Static Typing with Python
 *************************
 
-.. Introduction
-.. ============
-..
-.. .. toctree::
-..    :maxdepth: 2
-..
-..    source/introduction
-
 Guides
 ======
 

docs/source/annotations.rst

@@ -12,14 +12,3 @@ Type System Reference
    best_practices
    quality
    typing Module Documentation <https://docs.python.org/3/library/typing.html>
-
-.. The following pages are desired in a new TOC which will cover multiple
-.. topics. For now, they are not linked because the pages are empty.
-..
-..   basics
-..   type_system
-..   annotations
-..   inference
-..   type_compatibility
-..   dependencies
-..   faq