Remove mocha type reference in @opencensus/core release code (#254)

* Remove mocha type reference in production @opencensus/core code

* Make primary tsconfig include tests so IDEs get types

* Make default `compile` target still work

* Undo changes to main tsconfig.json

Author: draffensperger

packages/opencensus-core/package.json

@@ -11,8 +11,9 @@
     "clean": "rimraf build/*",
     "check": "gts check",
     "compile": "tsc -p .",
+    "compile:release": "tsc -p tsconfig-release.json",
     "fix": "gts fix",
-    "prepare": "npm run compile",
+    "prepare": "npm run compile:release",
     "pretest": "npm run compile",
     "posttest": "npm run check"
   },

packages/opencensus-core/tsconfig-release.json

@@ -0,0 +1,7 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "types": []
+  },
+  "include": ["src/**/*.ts"]
+}