Adapt README

Author: cedelavergne-ledger

README.md

@@ -2,17 +2,3 @@
 
 This repository is meant to be linked as submodule and used in external plugins working with [app-ethereum](https://github.com/LedgerHQ/app-ethereum).
 It is composed of a few headers containing definitions about app-ethereum's internal transaction parsing state and some structures to communicate via shared memory.
-
-## Updating this SDK
-
-This SDK is updated at (app-ethereum) build time every time one of app-ethereum internals structures of interest are modified.
-If this SDK gets updated, it is possible that all plugins must be recompiled (and eventually updated to work again with the update) with this new SDK.
-Be careful, and weight your choices.
-
-## Manual build
-
-If for some reasons you want to rebuild this SDK manually from [app-ethereum](https://github.com/LedgerHQ/app-ethereum) (reminder: it is rebuild automatically when building app-ethereum itself):
-
-```shell
-$> ./tools/build_sdk.sh
-```