s/stage/milestone/

"stage" is ambiguous with TC39 proposal stages. Roads ahead have milestones because road

Author: Dave Herman

roadmap.md

@@ -2,26 +2,26 @@
 
 ![The Road Ahead](http://img.archiwumallegro.pl/?1187401430)
 
-## Stage 0: Basic Static Loading
+## Milestone 0: Basic Static Loading
 
 - Name resolution (relative URLs, maybe absolute URLs)
 - Fetch integration
 - <script type="module">
 - memoization
 
-## Stage 1: Basic Dynamic Loading
+## Milestone 1: Basic Dynamic Loading
 
 - Worker invocation API
 - Dynamic (async) import API
 - Module instance object reflection
 - Relative import syntax (`import local from this;`)
 
-## Stage 2: Extensibility
+## Milestone 2: Extensibility
 
 - registry reflection
 - loading pipeline hooks
 
-## Stage 3: Conveniences
+## Milestone 3: Conveniences
 
 - Site packages