Work around a types issue in webvr. (#154)

This bug is not in Typescript < 3.0, so we force a version between 2.0 and 3.0 to not get hit by this bug in ci. Once it is fixed we can update to > 3.* eventually again.

microsoft/TypeScript#26038

Author: SirVer

octree_web_viewer/client/package-lock.json

@@ -15,7 +15,7 @@
     "@types/three": "0.0.27",
     "dat-gui": "0.5.0",
     "three": "0.83.0",
-    "typescript": "^2.2"
+    "typescript": "=2.7.2"
   },
   "prettier": {
     "arrow-parens": "always",

octree_web_viewer/client/package.json

@@ -14,7 +14,7 @@
     "rollup": "^0.55.3",
     "rollup-plugin-commonjs": "^8.3.0",
     "rollup-plugin-node-resolve": "^3.0.2",
-    "typescript": "^2.7.0"
+    "typescript": "=2.7.2"
   },
   "dependencies": {
     "@types/three": "0.91.8",