[android] Removed outdated docs

docs/android_toolchain.txt

@@ -1,37 +0,0 @@
-Windows:
-
-- Unzip NDK
-- Install Cygwin with gnu make and launch it
-$ export NDK_ROOT=C:/path/to/android-ndk-<version>
-$ export NDK_HOST=windows
-$ mkdir omim-android-debug
-$ cd omim-android-debug
-$ /cygdrive/path_to_QtSDK/path_to_Qt/mingw/bin/qmake.exe -r ../omim/omim.pro -spec ../omim/tools/mkspecs/android-g++ CONFIG+=debug
-$ /cygdrive/path_to_QtSDK/mingw/bin/mingw32-make.exe
-
-
-Mac OS X:
-
-- Unzip NDK
-- Create android-debug configuration in the QtCreator and set it's properties:
---- Shadow dir omim-android-<configuration>-armeabi
---- Override qmake parameters: -spec /path/to/omim/tools/mkspecs/android-g++
---- Set Environment variables
-    NDK_ROOT=/path/to/android-ndk-<version>
-    NDK_HOST=darwin-x86
-- Enjoy using QtCreator!
-
-
-!!!!! For any system !!!!!
-- See additional scripts and follow their instructions in <omim>/tools/android
---- Rename originat aapt file (<SDK>/platform_tools/aapt) to aapt2
---- Copy <omim>/tools/android/aapt to <SDK>/platform_tools/
---- Run <omim>/tools/android/update_assets.sh
-
-How to configure Debug/Release configurations in Eclipse:
-
-- Go to project properties/C++ build
-- Set additional parameter for ndk-build: NDK_DEBUG=1
-- Go to "manage configurations" at the top left and rename active Default configuration to Debug
-- Copy Debug configuration and rename it to Release
-- Change ndk-build's parameter NDK_DEBUG=1 to NDK_DEBUG=0 in Release