Change design of the app developed in react native and some funcionalities

Design changes:
1. Change login
2. Change filter layout
3. Change Listing layout
4. Change the icons of the share layout
Functionality
1 change the rest services to secure with oauth 2.0
Rest services list:
1. Login
2. get inventory
3. getcategories (this is new service)
4. Sign up (this is new functionality)