Updates to implement finish, process MultiSmartData for v1.2 (Mobile) SmartData and MultiValue workflow support.

If Series was updated by an attach, changing t0 or t1, it was not found with original parameters.  

Folder searcher renamed to filter. Search files nomeclature standard changed to f<id>, to recall filters and to follow the same nomeclature standard from workflows.
Options parameter renamed to 'filter'. The filter parameter contain an id field to specify which filter should be executed (default is 0). The field 'parameter' should be used to denote parameters specific to each filter, and will be parsed by filter itself.

Moreover, fixing SmartAPI search method to call the correct backend function.

A search API has been created.
The Backend and the SmartAPI has been modified to support the search functionalities.
A search recieves a series as a parameter, one that do not necessarily specifies a unit. Similar to a workflow, a search type is defined per domain. Moreover, a 'options' parameter is also expected, specifying which type of search will be performed. If options is not presented, search of index 0 will be executed.
A search returns a multi-unit series, ordered by timestamp.

An example for tutorial domain is provided, where through search0 anomalous temperature values are detected in the space-time range specified by the series parameter.

on mu_put.php and mv_put.php we changed instantiation of Backend to support requests with certificate.
on put.php the extra newline that php was complaining about was removed.
on Backend.php was changed to adjust create series (fix algorithm that merge series),
and some bug fixes on multi SmartData insertion.
on Series.php throw exception if invalid values of t0, t1 and r was changed to include the values of these parameters.
on MultiSmartData.php: bug fix on verifying existance of ->uncertainty and adding a parseJson method.
Also, files Backend.php and SmartAPI.php were changed to support get_activity.

Adjusting grafana interface as multiple fault injections were removed from documentation.

Update to support MultiSmartData in put.php

See merge request !7

Aggregators refactoring

See merge request !6

Aggregators were changed to remove dependency of range and reflect the documentation at: https://epos.lisha.ufsc.br/IoT+Platform#Data_Aggregation.

Reorganizing the repo structure to match the plan. Apparently, git filter-branch was not necessary to remove certificate's private key because someone had already run it. At least, git log --diff-filter=D --summary | grep delete does not show any private key.

Removing print used for tests. This can cause errors to the workflow output recognition by the API.