Update CLI docs to reflect new CLI verb/noun structure (#1031)

Use new CLI syntax

docs/developers/configs.md

@@ -6,7 +6,7 @@ These are ordered in order of preference, the later ones overriding the previous
 ## 1. Application level configuration
 
 ```sh
-fn apps config set myapp LOG_LEVEL debug
+fn config app myapp LOG_LEVEL debug
 ```
 
 ## 2. Function configuration from func.yaml
@@ -16,5 +16,5 @@ See [Function file](function-file.md) for more info.
 ## 3. Route level configuration
 
 ```sh
-fn routes config set myapp hello2 LOG_LEVEL info
+fn  config route myapp hello2 LOG_LEVEL info
 ```

docs/developers/usage.md

@@ -7,7 +7,7 @@ This is a more detailed explanation of the main commands you'll use in Fn as a d
 An application is essentially a grouping of functions, that put together, form an API. Here's how to create an app.
 
 ```sh
-fn apps create myapp
+fn create app myapp
 ```
 
 Or using a cURL:
@@ -29,7 +29,7 @@ A route is a way to define a path in your application that maps to a function. I
 can use -- yes, you can share functions! The source code for this function is in the [examples directory](/examples/hello/go).
 
 ```sh
-fn routes create myapp /hello -i fnproject/hello
+fn create route myapp /hello -i fnproject/hello
 ```
 
 Or using cURL: