Fixed redundant bootstrap explanation in doc

Author: inclement

doc/source/bootstraps.rst

@@ -11,56 +11,12 @@ components such as Android source code and various build files.
 If you do not want to modify p4a, you don't need to worry about
 bootstraps, just make sure you specify what modules you want to use
 (or specify an existing bootstrap manually), and p4a will
-automatically build everything appropriately. 
+automatically build everything appropriately. The existing choices are
+explained on the :ref:`build options <bootstrap_build_options>` page.
 
 This page describes the basics of how bootstraps work so that you can
 create and use your own if you like, making it easy to build new kinds
 of Python project for Android.
-
-
-Current bootstraps
-------------------
-
-python-for-android includes the following bootstraps by default, which
-may be chosen by name with a build parameter, or (by default) are
-selected automatically in order to fulfil your build requirements. For
-instance, if you add 'sdl2' in the requirements, the sdl2 backend will
-be used.
-
-p4a is designed to make it fairly easy to make your own bootstrap with a new backend,
-e.g. one that creates a webview interface and runs python in the
-background to serve a flask or django site from the phone itself.
-
-
-pygame
-%%%%%%
-
-This builds APKs exactly like the old p4a toolchain, using Pygame as
-the windowing and input backend.
-
-This bootstrap automatically includes pygame, kivy, and python. It
-could potentially be modified to work for non-Kivy projects.
-
-sdl2
-%%%%
-
-This builds APKs using SDL2 as the window and input backend. It is not
-fully developed compared to the Pygame backend, but has many
-advantages and will be the long term default.
-
-This bootstrap automatically includes SDL2, but nothing else.
-
-You can use the sdl2 bootstrap to seamlessly make a Kivy APK, but can
-also make Python apps using other libraries; for instance, using
-pysdl2 and pyopengl. `Vispy <http://vispy.org/>`_ also runs on android
-this way.
-
-empty
-%%%%%
-
-This bootstrap has no dependencies and cannot actually build an
-APK. It is useful for testing recipes without building unnecessary
-components.
 
 
 Creating a new bootstrap

doc/source/buildoptions.rst

@@ -56,6 +56,8 @@ the build is not fully optimised so APKs are probably a little larger
 and slower than they need to be. This is currently being addressed,
 though it's not clear how the final result will compare to python2.
 
+.. _bootstrap_build_options:
+
 Bootstrap
 ---------