Refactoring hash-object

Currently using mygit hash-object computes the object ID value for an object and writes the resulting object into the object database. It also reports its object ID to the standard output.

We do not want this to happen, hash-object should not write to the object database by default, make the changes accordingly so that this behavior is avoided.

If we wish to write to the object database then the -w flag is passed.

Keep in mind that there are other functions which use the hash-object function and write to the object database, when you make changes, make sure the other functions that use hash-object work like they used to previously.