[PHP] Add support for PHP7.

PHP5's C extension API has changed substantially so you need to use
-php7 to specify you want PHP7 compatible wrappers.
Fixes https://github.com/swig/swig/issues/571

Examples/test-suite/php5/li_carrays_cpp_runme.php

@@ -0,0 +1,22 @@
+<?php
+require "tests.php";
+require "li_carrays_cpp.php";
+
+// Check functions.
+check::functions(array(new_intarray,delete_intarray,intarray_getitem,intarray_setitem,doublearray_getitem,doublearray_setitem,doublearray_cast,doublearray_frompointer,xyarray_getitem,xyarray_setitem,xyarray_cast,xyarray_frompointer,delete_abarray,abarray_getitem,abarray_setitem));
+
+// Check classes.
+// NB An "li_carrays_cpp" class is created as a mock namespace.
+check::classes(array(li_carrays_cpp,doubleArray,AB,XY,XYArray));
+
+// Check global variables.
+check::globals(array(xy_x,xy_y,globalxyarray,ab_a,ab_b,globalabarray));
+
+$d = new doubleArray(10);
+
+$d->setitem(0, 7);
+$d->setitem(5, $d->getitem(0) + 3);
+check::equal($d->getitem(0) + $d->getitem(5), 17., "7+10==17");
+
+check::done();
+?>