Add "Reverse a number" Java Problem

[Diwakar-Gupta]

Issue Description:

This proposes adding the Reverse a number problem to our Java code repository.

Problem Statement

You can find the problem statement here

Implementation

Please read Contributing to Java Problems to get started with how to create new java problem and test for the same.

Note

For this problem you have to create a new folder with name problem32 inside folder javaProblems

[srujan0404]

please assign this issue to me sir

[Chay2203]

Please assign me this issue @probablyArth

[Chay2203]

This adds the following files in a new directory 'problem68' created inside the directory 'javaProblems' :

Solution.java
Test.java
readme.md

This fixes #68