[BUG] Double encoding on some page titles

[proditis]

Check the theme page titles. We need to ensure single encoding. Some data are double encoded on the theme page as well as the layout page.

On layouts/main.php: <title><?=trim(Html::encode($this->title))?></title>

Encoded title on the following views:

• material/profile/index.php
• material/profile/guest/index.php
• material/modules/tutorial/views/default/view.php
• material/modules/network/views/default/index.php
• material/modules/network/views/default/view.php
• material/modules/challenge/views/default/index.php
• material/modules/challenge/views/default/view.php
• material/modules/help/views/experience/index.php
• material/modules/help/views/faq/index.php
• material/modules/help/views/instruction/index.php
• material/modules/help/views/default/index.php
• material/modules/help/views/rule/index.php