reorganize examples

examples/README.md

@@ -1,18 +1,35 @@
 # Examples
 
+
+## Simple
 - [hello world](./hello-world.md) - simple hello world
+
+
+## Function
 - [function hello world](./function-hello-world.md) - hello world but leveraging javascript interpreter
 - [function option](./function-option-params.md) - passing option params to a nca command
 - [function positional arguments](./function-positional-arguments.md) - passing positional arguments to a nca command
 - [function shell command execution](./function-shell-command-execution.md) - executing shell commands leveraging shelljs
+
+
+## Modules
 - [js modules hello world](./module-hello-world.md) - declaring and mantainig complex js scripts in yml could become unsustainable. This example shows how to directly execute a javascript module.
 - [js modules complex](./module-complex.md) - using option and positional arguments with javascript modules
 - [js modules shell command execution](./module-shell-command-execution.md) - executing shell commands leveraging shelljs inside javascript modules
 - [js modules external npm dependencies](./module-external-dependencies.md) - executing js scripts which use external npm dependencies
-- [hierarchy](./hierarchy.md) - creating nca command hierarchies, to create complex command line interfaces
+
+
+## Custom completion
 - [custom static completion](./custom-static-array-completion.md) - override yargs shell completion with a custom one statically defined
 - [custom js completion](./custom-js-completion.md) - override yargs shell completion with a custom one returned by invoking a custom js module
 - [custom js input completion](./custom-js-input-completion.md) - override yargs shell completion with a custom one returned by invoking a custom js module. It uses current command line status to determine what to return
+
+
+## Advanced
+- [hierarchy](./hierarchy.md) - creating nca command hierarchies, to create complex command line interfaces
 - [alias](./alias.md) - create an alias for a long nca command or to use a nca command without typing `nca` prefix
+
+
+## Other
 - [my nca commands](https://github.com/gturi/nca-commands) - git repo where I track the nca commands I use
 - [tests](../test/integration) - nca commands used for integration tests