[UPDATE] new feature (audit) and enhancements

[UPDATE] new feature (audit) and enhancements

Audit is a new feature which allows to determine what takes most of the
generation time during the whole generation process. It stores
informations (calls number, time spent and last call time) so that each
call can be audited. Audit is filled calling
WsdlTophpgenerator::auditInit() at function start then
WsdlTophpgenerator::audit() to calculate time spent and calls number.
Audit informations are stored using the WsdlToPhpGenerator global
storage data. Audit can be accessed using the
WsdlToPhpGenerator::getAudit() method which returns an associative array
of all audited calls.

Improve inheritance determination, operation return and parameter types
determination by browsing schemas sequentially in order to retrieve
several particular tags (header, list, union, attribute, input, output).
See WsdlToPhpGenerator::wsdlsLoaded(). The generated php doc is then
more precise and informations are retrieved when the SoapClient object
doesn't retrieve hem.

Improve location management system in order to allow local schemas file
loading.

Minor review of attributes declaration for WsdlToPhpModel type classes.

Minor review of documentation management for php doc.