Created exercises

- Added endpoint to retrieve the list of exercises

app/Exercise.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace App;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Exercise extends Model
+{
+    /**
+     * The name of the exercise
+     * @var string
+     */
+    protected $name;
+
+    /**
+     * The attributes that are mass assignable.
+     *
+     * @var array
+     */
+    protected $fillable = [
+        'name'
+    ];
+
+    /**
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * @param string $name
+     */
+    public function setName(string $name): void
+    {
+        $this->name = $name;
+    }
+}