Extend this directory for Data Structures in Java Language

[KrishJani]

I really like the initiative of this repo. I want to extend it furthermore so that students proficient in the java language can use this.

this is what ill do..

• [X] Create a new directory with name "Data structures in Java"
• [X] Add implementation of LinkedList in it (java file)
• [X] Add implementation of BinaryTree in it (java file)
• [X] Create another directory in it where people can add top DSA questions in java

If my idea sounds good, then kindly assign me to this and add hacktoberfest tags to it.

[rohith1125]

@KrishJani permission granted proceed as mentioned