Changes

tsk11 Adds service method for searching stories
Adds method on stories service for searching by title or content. The
results will be paginated using two parameters for set the number of
pages and the number of results per page. By default, values are 0 and
0, so it returns page 0 with 10 results. Results are ordered by
publication date. Adds tests for this method, due to this dataset is
modified to create needed test methods.