feat: add php solution to lc problem: No.1451 (#1020)

Author: Qiu-IT

solution/1400-1499/1451.Rearrange Words in a Sentence/README.md

@@ -137,6 +137,31 @@ func arrangeWords(text string) string {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $text
+     * @return String
+     */
+    function arrangeWords($text) {
+        $text = lcfirst($text);
+        $arr = explode(" ", $text);
+        for ($i = 0; $i < count($arr); $i++) {
+            $hashtable[$i] = strlen($arr[$i]);
+        }
+        asort($hashtable);
+        $key = array_keys($hashtable);
+        $rs = [];
+        for ($j = 0; $j < count($key); $j++) {
+            array_push($rs, $arr[$key[$j]]);
+        }
+        return ucfirst(implode(" ", $rs));
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1400-1499/1451.Rearrange Words in a Sentence/README_EN.md

@@ -122,6 +122,31 @@ func arrangeWords(text string) string {
 }
 ```
 
+### **PHP**
+
+```php
+class Solution {
+    /**
+     * @param String $text
+     * @return String
+     */
+    function arrangeWords($text) {
+        $text = lcfirst($text);
+        $arr = explode(" ", $text);
+        for ($i = 0; $i < count($arr); $i++) {
+            $hashtable[$i] = strlen($arr[$i]);
+        }
+        asort($hashtable);
+        $key = array_keys($hashtable);
+        $rs = [];
+        for ($j = 0; $j < count($key); $j++) {
+            array_push($rs, $arr[$key[$j]]);
+        }
+        return ucfirst(implode(" ", $rs));
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1400-1499/1451.Rearrange Words in a Sentence/Solution.php

@@ -0,0 +1,20 @@
+class Solution {
+    /**
+     * @param String $text
+     * @return String
+     */
+    function arrangeWords($text) {
+        $text = lcfirst($text);
+        $arr = explode(" ", $text);
+        for ($i = 0; $i < count($arr); $i++) {
+            $hashtable[$i] = strlen($arr[$i]);
+        }
+        asort($hashtable);
+        $key = array_keys($hashtable);
+        $rs = [];
+        for ($j = 0; $j < count($key); $j++) {
+            array_push($rs, $arr[$key[$j]]);
+        }
+        return ucfirst(implode(" ", $rs));
+    }
+}