add plugins info and dev rules(copied from plugins/README) (#124)

add plugins info and dev rules(copied from plugins/README)

index.rst

@@ -19,6 +19,8 @@ Electrum is a lightweight Bitcoin wallet.
    coldstorage
    hardware-linux
    tails
+   plugins
+
 
 .. toctree::
    :maxdepth: 2
@@ -50,3 +52,4 @@ Electrum is a lightweight Bitcoin wallet.
    seedphrase
    protocol
    transactions
+   plugin_rules

plugin_rules.rst

@@ -0,0 +1,32 @@
+Plugin rules:
+=============
+
+ * The plugin system of Electrum is designed to allow the development
+   of new features without increasing the core code of Electrum.
+
+ * Electrum is written in pure python. if you want to add a feature
+   that requires non-python libraries, then it must be submitted as a
+   plugin. If the feature you want to add requires communication with
+   a remote server (not an Electrum server), then it should be a
+   plugin as well. If the feature you want to add introduces new
+   dependencies in the code, then it should probably be a plugin.
+
+ * We expect plugin developers to maintain their plugin code. However,
+   once a plugin is merged in Electrum, we will have to maintain it
+   too, because changes in the Electrum code often require updates in
+   the plugin code. Therefore, plugins have to be easy to maintain. If
+   we believe that a plugin will create too much maintenance work in
+   the future, it will be rejected.
+
+ * Plugins should be compatible with Electrum's conventions. If your
+   plugin does not fit with Electrum's architecture, or if we believe
+   that it will create too much maintenance work, it will not be
+   accepted. In particular, do not duplicate existing Electrum code in
+   your plugin.
+
+ * We may decide to remove a plugin after it has been merged in
+   Electrum. For this reason, a plugin must be easily removable,
+   without putting at risk the user's bitcoins. If we feel that a
+   plugin cannot be removed without threatening users who rely on it,
+   we will not merge it.
+

plugins.rst

@@ -0,0 +1,55 @@
+Plugins
+=======
+
+The plugin system of Electrum is designed to allow the development of new features without increasing the core code of Electrum. To enable or disable Plugins, see menubar > `Tools` > `Plugins`. 
+
+Below you can find a short description of each available tool. 
+
+
+Audio Modem
+-----------
+
+Provides support for air-gapped transaction signing.
+requires 'amodem' python package http://github.com/romanz/amodem/
+
+
+Cosigner Pool
+-------------
+
+This plugin facilitates the use of multi-signatures wallets. It sends and receives partially signed transactions from/to your cosigner wallet. Transactions are encrypted and stored on a remote server.
+
+
+Email	
+-----
+
+Send and receive payment request with an email account
+keys.
+
+
+LabelSync
+---------
+
+Save your wallet labels on a remote server, and synchronize them across multiple devices where you use Electrum. Labels, transactions IDs and addresses are encrypted before they are sent to the remote server.
+
+
+Revealer
+--------
+
+This plug-in allows you to create a visually encrypted backup of your wallet seeds, or of custom alphanumeric secrets.
+
+
+Two Factor Authentication
+-------------------------
+
+This plugin adds two-factor authentication to your wallet.
+For more information, visit https://api.trustedcoin.com/#/electrum-help
+
+
+
+Virtual Keyboard
+----------------
+
+Add an optional virtual keyboard to the password dialog.
+Warning: do not use this if it makes you pick a weaker password.
+
+