More sorting techniques added

New methods added corresponding to the following sorting techniques:

• Insertion Sort
• Selection Sort
• Quick Sort
• Merge Sort

Travis CI integration to test builds

• Integrated Travis CI
• Added multi-platform support

Initial Release: Bubble Sort

• This is the initial release that contains a single sorting technique (Bubble sort).
• A private method to internally check if array is already sorted or not before attempting to sort it.
• Specs cover both methods.