* dibs : I will implement exercise bookstore

* bookstore : add to track

* bookstore : add to track

 update config.json

* Update config.json : added orc-numbers

* add missing test from the canonical spec and delete the remaning test

* using camelCase instead of snake_case for tests methods

* adding @Ignore annotation

* using List instead of ArrayList

* using instance methods instead of class method

* delete useless stuff

* modify magic numbers

* update CostPerGroup method

* update class name and files name to Bookstore from Bookstore  + using camelCase for methods

* pass the integers directly to the Arrays.asList() methods

* adding brackets

* fix constant variable

* using static for constants

* dibs: I will implement exercise isogram

* isogram: add to track

* isogram: add to track

* improve Isogram implementation

* Isogram: adjust API to use instance methods

* Improve Isogram implementation

* Added list-ops exercise to the Java track
* Removed NetBeans settings from the project dir
* Added collect() operation and tests

* dibs: I will implement exercise Clock

* Implemented clock exercise

* dibs: I will implement custom-set

* Created an empty project

* Added custom-set exercise to the Java track

* Added palindrome-products exercise to the Java track

* Added @Ignore annotations to tests

* Added binary search tree exercise to the Java track

* Removed pythagorial triplet from config.json

* Removed binary search from config.json

- This code is the solution for the un-implemented Sum of Multiple
problem.
- Includes Test File which checks each test case indicated here:
https://github.com/exercism/x-common/blob/master/exercises/sum-of-multip
les/canonical-data.json

With exercism/exercism.io@54e1df3, we can now gather exercises into a
subdirectory. By separating the language track files from the
configuration and management files, it is easier to read the project.

- move gradle config under "exercises" too as it would make a mess
  otherwise.

Tests and example implementation based on the ruby exercise.

Completes a task for https://github.com/exercism/xjava/issues/3.

Apply generics to the internals of Element to remove
needless casting.

Tighten Element scoping and move into Deque for succintness (sp).

Add the execise into the grade test suite.

This implementation does not generate a test suite based on the json
meta the hello-world exercise.
See https://github.com/exercism/todo/issues/13

Fixes https://github.com/exercism/todo/issues/35

- where files are required from the "starter" (./src/main/java), these
  are now soft-linked into the example source.
- a couple examples were missing import statements.
- the example code for Hamming was failing the test suite.

At this time, these are all of the problems that have example code.