Use @psalm-template annotation to avoid clashes

[muglug]

Following reports that some users encountered issues with @template annotations, this PR replaces @template with the functionally-equivalent @psalm-template.

[Ocramius]

Verified via following script:

<?php

declare(strict_types=1);

namespace A;

use Doctrine\Common\Annotations\AnnotationReader;
use Doctrine\Common\Collections\Collection;

(function () {
    require_once __DIR__ . '/vendor/autoload.php';

    AnnotationReader::addGlobalIgnoredName('psalm');

    $reader = new AnnotationReader();

    var_dump($reader->getClassAnnotations(new \ReflectionClass(Collection::class)));
})();

Produces:

php check-patch-186.php 
array(0) {
}

[Ocramius]

Backported to 1.6 via 688aef6