Add doc

README.md

@@ -4,25 +4,22 @@ TODO: Write a description here
 
 ## Installation
 
-TODO: Write installation instructions here
+Make sure you have Crystal and Make installed on your system.
+
+Then type
+
+```shell-session
+$ make build
+```
 
 ## Usage
 
+```shell-session
+$ ./_build/kathmandu_time 21:30
+Paris:     21:30 +02:00
+Kathmandu: 01:11 +05:41
+```
 
-TODO: Write usage instructions here
+## Authors
-
-## Development
-
-TODO: Write development instructions here
-
-## Contributing
-
-1. Fork it (<https://github.com/glenux/./fork>)
-2. Create your feature branch (`git checkout -b my-new-feature`)
-3. Commit your changes (`git commit -am 'Add some feature'`)
-4. Push to the branch (`git push origin my-new-feature`)
-5. Create a new Pull Request
-
-## Contributors
 
 - [Glenn Y. Rolland](https://github.com/glenux) - creator and maintainer