* Fix storage leak in builder
```
builder pod keeps old src and deployment packages irrespective of build status.
delete src package after every build request is completed.
delete deployment package after package is uploaded.
```
* Optimized src/deploy cleanup pkg code
* Fix high severity security issue
* Add a test for builder's Clean API
* Resolve review comments
---------
Signed-off-by: Md Soharab Ansari <soharab.ansari@infracloud.io>
