Add examples to README (#9)

README.md

@@ -1 +1,36 @@
-# ewcli
+# ewcli
+
+ewcli it's a small tool to simplify some day to day tasks such as getting
+environment variables with AWS credentals from an AWS SAML assertion.
+
+## Usage
+
+ewcli it's based on subcommands, at the moment is only available the `aws saml`
+subcommand.
+
+### ewcli aws saml
+
+```
+Usage:
+  ewcli aws saml [flags]
+
+Flags:
+  -h, --help                     help for saml
+      --print-env-creds          Print Credentials as Environment Variables
+  -a, --saml-account-id string   Pass an AWS Account ID
+  -f, --saml-file string         Pass a path to the file that contains SAML Assertion (default "/tmp/saml")
+      --saml-role-name string    Pass an AWS IAM Role Name
+
+Global Flags:
+      --config string   config file (default is $HOME/.ewcli.yaml)
+  -r, --region string   Pass an AWS region (default "us-east-1")
+```
+
+#### Example
+
+``` sh
+> ewcli aws saml -f /tmp/saml --saml-account-id 123456789 --saml-role-name GoogleReadOnlyAccess --print-env-creds                                                                                  
+export AWS_ACCESS_KEY_ID=...
+export AWS_SECRET_ACCESS_KEY=...
+export AWS_SESSION_TOKEN=...
+```