Update package description

Author: docd27

package.json

@@ -1,15 +1,22 @@
 {
   "name": "rollup-plugin-glsl-optimize",
   "version": "0.0.7",
-  "description": "Import GLSL source files. Pre-processed, validated and optimized with Khronos Group SPIRV-Tools.",
+  "description": "Import GLSL source files as strings. Pre-processed, validated and optimized with Khronos Group SPIRV-Tools.",
   "homepage": "https://github.com/docd27/rollup-plugin-glsl-optimize#readme",
   "keywords": [
     "rollup",
     "plugin",
     "glsl",
+    "glslang",
     "webgl",
+    "webgl2",
+    "shader",
     "shaders",
-    "optimize"
+    "optimize",
+    "vert",
+    "frag",
+    "spirv",
+    "spir-v"
   ],
   "author": "docd27",
   "repository": {