(feat) add support for highlighting js/ts/coffee in style blocks (#1318)

Partially deals with #1248

This doesn't add anything like autocompletion or semantic highlighting, but if there are people using these kind of libraries with Svelte, at least the highlighting, indentation, etc. will be present.

Author: Monkatraz

packages/svelte-vscode/syntaxes/svelte.tmLanguage.src.yaml

@@ -13,22 +13,23 @@ injections:
   #     patterns: [{begin: '(?<=>)(?!</)', end: '(?=</)', name: meta.embedded.block.svelte,
   #     contentName: source.<lang>, patterns: [{ include: source.<lang> }]}]
 
-  # Script Languages
+  # Style/Script Languages
   # JavaScript | 'javascript' | 'source.js'
-  'L:meta.script.svelte meta.lang.javascript - (meta source)':
+  'L:(meta.script.svelte | meta.style.svelte) (meta.lang.js | meta.lang.javascript) - (meta source)':
     patterns: [{begin: '(?<=>)(?!</)', end: '(?=</)', name: meta.embedded.block.svelte,
     contentName: source.js, patterns: [{ include: source.js }]}]
 
   # TypeScript | 'ts' 'typescript' | 'source.ts'
-  'L:meta.script.svelte (meta.lang.ts | meta.lang.typescript) - (meta source)':
+  'L:(meta.script.svelte | meta.style.svelte) (meta.lang.ts | meta.lang.typescript) - (meta source)':
     patterns: [{begin: '(?<=>)(?!</)', end: '(?=</)', name: meta.embedded.block.svelte,
     contentName: source.ts, patterns: [{ include: source.ts }]}]
 
   # CoffeeScript | 'coffee' | 'source.coffee'
-  'L:meta.script.svelte meta.lang.coffee - (meta source)':
+  'L:(meta.script.svelte | meta.style.svelte) meta.lang.coffee - (meta source)':
     patterns: [{begin: '(?<=>)(?!</)', end: '(?=</)', name: meta.embedded.block.svelte,
     contentName: source.coffee, patterns: [{ include: source.coffee }]}]
 
+  # Script Languages
   # Default (JavaScript)
   'L:meta.script.svelte - meta.lang - (meta source)':
     patterns: [{begin: '(?<=>)(?!</)', end: '(?=</)', name: meta.embedded.block.svelte,