Default ignores/.exoframeignore doesn't work on Windows (#289)

* Default ignores/.exoframeignore doesn't work on Windows

Closes #284

Author: FDiskas

.gitignore

@@ -11,3 +11,4 @@ dist/
 
 package-lock.json
 exoframe.json
+yarn.lock

src/commands/deploy.js

@@ -183,7 +183,7 @@ exports.handler = async (args = {}) => {
   const tarStream = tar.pack(workdir, {
     // ignore files from ignore list
     ignore: name => {
-      const relativePath = name.replace(`${workdir}/`, '');
+      const relativePath = path.relative(workdir, name);
       const result = multimatch([relativePath], ignores).length !== 0;
       return result;
     },