fix: missing resource methods (#31)

This will ensure that `resource` methods are proper highlighted
(including `constructor`). There are several small improvements to the
grammar to improve maintainability as well.

Author: eduardomourar

README.md

@@ -7,9 +7,13 @@ The description of the WIT format can be found at: https://github.com/WebAssembl
 
 ## Features
 
-This extension provides basic syntax highlighting of ".wit" files.
+![Screenshot](images/screenshot.png)
 
-Additionally, it provides [Snippets](https://code.visualstudio.com/docs/editor/userdefinedsnippets).
+This extension provides:
+- Basic syntax highlighting of ".wit" files.
+- [Snippets](https://code.visualstudio.com/docs/editor/userdefinedsnippets) for worlds and interfaces.
+- Basic markdown highlighting in comments.
+- Simple list-based autocomplete.
 
 ## Installation
 

images/screenshot.png

@@ -6,7 +6,7 @@
   },
   "Add World": {
     "prefix": "world ",
-    "body": "world ${1:my-world} {\n  import ${2:my-input}: foo.bar\n  export ${3:my-output}: func() -> u32\n}",
+    "body": "world ${1:my-world} {\n  import ${2:my-input}: foo\n  export ${3:my-output}: func() -> u32\n}",
     "description": "Adds a simple world"
   }
 }