docs: More README updates

Author: nritholtz

README.md

@@ -2,18 +2,6 @@
 
 Terrafile is a binary written in Go to systematically manage external modules from Github for use in Terraform. See this [article](http://bensnape.com/2016/01/14/terraform-design-patterns-the-terrafile/) for more information on how it was introduced in a Ruby rake task.
 
-This is currently an experimental WIP.
-
-An example Terrafile:
-```
-tf-aws-vpc:
-    source:  "[email protected]:terraform-aws-modules/terraform-aws-vpc"
-    version: "v1.46.0"
-tf-aws-vpc-experimental:
-    source:  "[email protected]:terraform-aws-modules/terraform-aws-vpc"
-    version: "master"
-```
-
 ## How to install
 
 ### macOS
@@ -31,22 +19,33 @@ curl -L https://github.com/coretech/terrafile/releases/download/v0.3/terrafile_0
 ```
 
 ## How to use
+Terrafile expects a file named `Terrafile` which will contain your terraform module dependencies in a yaml like format.
+
+An example Terrafile:
+```
+tf-aws-vpc:
+    source:  "[email protected]:terraform-aws-modules/terraform-aws-vpc"
+    version: "v1.46.0"
+tf-aws-vpc-experimental:
+    source:  "[email protected]:terraform-aws-modules/terraform-aws-vpc"
+    version: "master"
+```
 
-Terrafile config in current directory and modules exported to ./vendor/modules
+Terrafile config file in current directory and modules exported to ./vendor/modules
 ```sh
 $ terrafile
 INFO[0000] [*] Checking out v1.46.0 of [email protected]:terraform-aws-modules/terraform-aws-vpc  
 INFO[0000] [*] Checking out master of [email protected]:terraform-aws-modules/terraform-aws-vpc  
 ```
 
-Terrafile config in custom location
+Terrafile config file in custom directory
 ```sh
 $ terrafile -f config/
 INFO[0000] [*] Checking out v1.46.0 of [email protected]:terraform-aws-modules/terraform-aws-vpc  
 INFO[0000] [*] Checking out master of [email protected]:terraform-aws-modules/terraform-aws-vpc  
 ```
 
-Terraform modules exported to custom location
+Terraform modules exported to custom directory
 ```sh
 $ terrafile -p custom_directory
 INFO[0000] [*] Checking out master of [email protected]:terraform-aws-modules/terraform-aws-vpc