add initial readme file

Signed-off-by: Jakub Sokołowski <jakub@status.im>

README.md

@@ -0,0 +1,28 @@
+# Description
+
+This role configures a `geth`([go-ethereum](https://github.com/ethereum/go-ethereum)) container.
+
+The image used by default is [ethereum/client-go](https://hub.docker.com/r/ethereum/client-go/).
+
+# Configuration
+
+The only mandaotry settings is the account password, which can be set to an empty string:
+
+```yaml
+geth_account_password: 'my-secret-password'
+```
+
+Other important settings are:
+
+```yaml
+geth_network_name: 'mainnet'
+geth_sync_mode: 'full'
+geth_log_level: 3
+geth_consul_tags: '{{ geth_consul_tags + ["mytag"] }}'
+```
+
+For the rest see the [`defaults/main.yml`](/defaults/main.yml) config file.
+
+# Known Issues
+
+__TODO__