Improved getting actual PHP version for AppVeyor

[sergeyklay]

As I can see the PHP.net team experiences some bandwidth issues for the http://windows.php.net website. Therefore, they decided to block all requests without User-Agent.

20/feb/2018: Hi! We seem to be receiving high volume requests coming from empty user agents. While this shouldn't be an issue, this unfortunately resulted in bandwidth issues on this server causing all downloads to be unavailable. We've therefore decided to temporarily block empty user agents until we upgraded our server bandwidth.

03/mar/2018: We've upgraded the server bandwidth. This is however still not sufficient to handle all empty user agent connections. Please update the user agent in your scripts accordingly or contact us so we can discuss it.

Thank you for your understanding.

[coveralls]

Coverage remained the same at 100.0% when pulling 33eedfc on phalcon:fix/appveyor-install-php into 5de43f2 on jbboehr:master.

[coveralls]

Coverage remained the same at 100.0% when pulling fb102ba on phalcon:fix/appveyor-install-php into 5de43f2 on jbboehr:master.

[sergeyklay]

@jbboehr Could you please take a look? :)

[jbboehr]

@sergeyklay You added these to the appveyor cache, correct?

[sergeyklay]

@jbboehr Do you mean php archive and dependencies? Yes, I added all this to the AppVeyor cache