SPARK-3009: Reverted readObject method in ApplicationInfo so that Applic...

...ationInfo is initialized properly after deserialization

Author: Jacek Lewandowski <lewandowski.jacek@gmail.com>

Closes #1922 from jacek-lewandowski/branch-1.0 and squashes the following commits:

13c1fb3 [Jacek Lewandowski] SPARK-3009: Reverted readObject method in ApplicationInfo so that ApplicationInfo is initialized properly after deserialization