fix: produce posix path in windows

closes #5

Author: danielpza

package-lock.json

@@ -29,9 +29,12 @@
     "release": "standard-version",
     "test": "ttsc -p tests/tsconfig.json && node tests/core/index.js"
   },
-  "dependencies": {},
+  "dependencies": {
+    "slash": "^2.0.0"
+  },
   "devDependencies": {
     "@types/node": "^10.12.21",
+    "@types/slash": "^2.0.0",
     "standard-version": "^4.4.0",
     "ttypescript": "^1.5.6",
     "typescript": "^3.2.4"

package.json

@@ -1,5 +1,6 @@
 import * as ts from "typescript";
 import { dirname, resolve, relative } from "path";
+import slash = require("slash");
 
 const transformer = <T extends ts.Node>(_: ts.Program) => {
   return (context: ts.TransformationContext) => (rootNode: T) => {
@@ -25,7 +26,7 @@ const transformer = <T extends ts.Node>(_: ts.Program) => {
           const match = node.moduleSpecifier.text.match(path.regexp);
           if (match === null) continue;
           const out = path.resolve.replace(/\*/g, match[1]);
-          const file = relative(fileDir, resolve(baseUrl, out));
+          const file = slash(relative(fileDir, resolve(baseUrl, out)));
           return ts.updateImportDeclaration(
             node,
             node.decorators,