Refactor readers for better di (#457)

* Refactor readers to get a proper DI

Similar to what was done with writers, readers also needed to be updated to match the new way of doing things.
This commits promotes a better DI (factories, injection through constructors).

* Escapers should not be singletons

Instead, they should be proper object that can be injected where needed.

tests/Spout/Common/Helper/Escaper/XLSXTest.php

@@ -0,0 +1,83 @@
+<?php
+
+namespace Box\Spout\Common\Helper\Escaper;
+
+use Box\Spout\Common\Helper\Escaper;
+
+/**
+ * Class XLSXTest
+ *
+ * @package Box\Spout\Common\Helper\Escaper
+ */
+class XLSXTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @return array
+     */
+    public function dataProviderForTestEscape()
+    {
+        return [
+            ['test', 'test'],
+            ['adam\'s "car"', 'adam\'s "car"'],
+            ["\n", "\n"],
+            ["\r", "\r"],
+            ["\t", "\t"],
+            [chr(0), '_x0000_'],
+            [chr(4), '_x0004_'],
+            ['_x0000_', '_x005F_x0000_'],
+            [chr(21), '_x0015_'],
+            ['control '.chr(21).' character', 'control _x0015_ character'],
+            ['control\'s '.chr(21).' "character"', 'control\'s _x0015_ "character"'],
+        ];
+    }
+
+    /**
+     * @dataProvider dataProviderForTestEscape
+     *
+     * @param string $stringToEscape
+     * @param string $expectedEscapedString
+     * @return void
+     */
+    public function testEscape($stringToEscape, $expectedEscapedString)
+    {
+        $escaper = new Escaper\XLSX();
+        $escapedString = $escaper->escape($stringToEscape);
+
+        $this->assertEquals($expectedEscapedString, $escapedString, 'Incorrect escaped string');
+    }
+
+    /**
+     * @return array
+     */
+    public function dataProviderForTestUnescape()
+    {
+        return [
+            ['test', 'test'],
+            ['adam&#039;s &quot;car&quot;', 'adam&#039;s &quot;car&quot;'],
+            ["\n", "\n"],
+            ["\r", "\r"],
+            ["\t", "\t"],
+            ['_x0000_', chr(0)],
+            ['_x0004_', chr(4)],
+            ['_x005F_x0000_', '_x0000_'],
+            ['_x0015_', chr(21)],
+            ['control _x0015_ character', 'control '.chr(21).' character'],
+            ['control&#039;s _x0015_ &quot;character&quot;', 'control&#039;s '.chr(21).' &quot;character&quot;'],
+        ];
+    }
+
+    /**
+     * @dataProvider dataProviderForTestUnescape
+     *
+     * @param string $stringToUnescape
+     * @param string $expectedUnescapedString
+     * @return void
+     */
+    public function testUnescape($stringToUnescape, $expectedUnescapedString)
+    {
+        $escaper = new Escaper\XLSX();
+        $unescapedString = $escaper->unescape($stringToUnescape);
+
+        $this->assertEquals($expectedUnescapedString, $unescapedString, 'Incorrect escaped string');
+    }
+}