Proposal #1: ServiceBox action servlet with Spring Framework

* Include Spring dependencies
* Remove unused servlets
* Implement a generic Servlet to allow to add callbacks for each servlet GET/POST
* Include Jackson dependency for the write error method on Utilities class.
* FileUploadCallback to limit file items size and length
* Include file types regexp for the file uploader callback.
* Improve the File upload callback and Utilities class with a error model in JSON for MapStore localization.
* Improve the service box handler implementation to read servlet class simple name as default actionName
* Change the servlets: FileUploadCallback, FileUploader, HTTPWebGISFileUpload, HTTPWebGISSave, ServiceBoxActionServlet, UploadCanvas and KMZUploader in order to use the new action servlet.
* Check if the temporal folder exists and create it if it doesn't
* This commit fixes geosolutions-it/mapstore#138.

This changes are related to geosolutions-it/mapstore#138 issue and the proposal: https://github.com/geosolutions-it/servicebox/wiki/Proposal-%231:-ServiceBox-action-servlet-with-Spring-Framework