Changes

tsk28 Creates the entity Visit
Creates the Visit entity to record all the visits made to a specific
story, saving the date on which it is made

tsk28 Adds the tests for the entity Visit
Adds the necessary tests to verify that the Visit entity is not faulty
and is working correctly

tsk28 Adds to the entity Story the attribute visits
Adds to the Story entity as an attribute the list of visits, and removes
the previous visits attribute

tsk28 Modifies the Story entity tests to adapt them to the new attribute
visits
Modifies the Story entity tests by deleting the old visits attribute,
replacing it with the new one

tsk28 Modifies service and rest tests to remove references to old
attribute visits
Modifies test files to remove references to the old visits attribute to
avoid integration problems with the new entity and attribute

tsk28 Modifies the database scripts with the new entity
Modifies the database scripts to remove the old attribute and add the
new entity. The creation, deletion, reset and example data of the new
entity is added.

tsk28 Adds the Visit entity tests to the entity TestSuite
Adds the class with the Visit entity tests to the entity TestSuite

tsk28 Deletes test database creation script
Removes test database creation script that is no longer needed, since
the visits attribute does not exist as an integer in the Story entity.