Updated version of fxp/composer-asset-plugin in installation guide after testing new version. It's faster!

Fixes #5598: added ImageMagick with PNG and GD with FreeType checks to requirements of basic and advanced applications, used better Captcha exception message

update caching-fragment.md [skip ci]

to avoid issues about 404 links in the guide

Docs ja 2014 10 18

make sure to not confuse extending of helper classes with extensions.
Use "customizing" in this case and added note about when this should be done.

correct a error link [skip ci]

Update runtime-responses.md [skip ci]

Update old files and add some new translations

fixes #5623

fixes #5601

[ci skip] Update runtime-responses.md

[skip ci] Update Object.php

updated runtime-sessions-cookies.md [skip ci]

refactoring code

Fixed the bug that Gii console command help information does not contain global options

In modest my opinion this should be ' : ' instead of ' , ' [skip ci]

fixes #5580