fixes #743

* master: (806 commits)
  avoid confusing docs about autoload return value
  doc fix.
  Fixed doc.
  Fixed autoloader behavior according to leading \
  Fix in RequestPanel
  changed to trace from info.
  Removed yii\debug\Module::enabled.
  minor enhancement of debugger.
  Refactored the basic app.
  Added ErrorAction.
  Use `hasAttribute()` instead to avoid code duplication
  refactored NavBar and basic app navbar.
  test break fix.
  test break fix.
  Fixed test breaks.
  #735: removed hiddenInput to avoid confusion.
  ResizableAsset typo fix!
  Update radio and checkbox due to e3801fbf
  css fix.
  Fixed the basic app template.
  ...

Conflicts:
	.travis.yml
	tests/unit/data/config.php

autoload return value has no effect on other autoloaders
they will only be called based on whether the class has been loaded or
not.

Fixed autoloader behavior according to leading \

As of PHP 5.3.2 PHP does not send class names with leading \ to
autoload functions.

Removed ltrim for '/' from autoload because it is

1. not needed: https://bugs.php.net/bug.php?id=50731 and
2. possibly wrong behavior: https://bugs.php.net/bug.php?id=51087

Fix in RequestPanel

Use `hasAttribute()` instead to avoid code duplication

Update radio and checkbox

ResizableAsset typo fix!

fixes initializing attributes in Sort class

fix typos - `Yii::app()`

Add more readme badges. Fix #726.