added examples/php/load-all-at-once.php fix ccxt#730

examples/php/load-all-at-once.php

@@ -0,0 +1,42 @@
+<?php
+
+$root = dirname (dirname (dirname (__FILE__)));
+
+include $root . '/ccxt.php';
+
+date_default_timezone_set ('UTC');
+
+$exchanges = \ccxt\Exchange::$exchanges;
+
+foreach ($exchanges as $exchange) {
+    $id = "\\ccxt\\".$exchange;
+    $exchange = new $id();
+    echo "--------------------------------------------\n";
+    echo $exchange->id . "\n";
+
+    try {
+        $markets = $exchange->load_markets ();
+        echo count (array_values ($exchange->markets)) . " markets: " .
+            implode (', ', array_slice ($exchange->symbols, 0, 5)) . "...\n";
+    } catch (\ccxt\RequestTimeout $e) {
+        echo '[Timeout Error] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\DDoSProtection $e) {
+        echo '[DDoS Protection Error] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\AuthenticationError $e) {
+        echo '[Authentication Error] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\ExchangeNotAvailable $e) {
+        echo '[Exchange Not Available] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\NotSupported $e) {
+        echo '[Not Supported] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\NetworkError $e) {
+        echo '[Network Error] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (\ccxt\ExchangeError $e) {
+        echo '[Exchange Error] ' . $e->getMessage () . ' (ignoring)' . "\n";
+    } catch (Exception $e) {
+        echo '[Error] ' . $e->getMessage () . "\n";
+    }
+    echo "\n";
+}
+
+
+?>