Add more friendly Plugin/Theme info

[meloniq]

Add some more friendly Plugin/Theme info... when update is available, and user click 'View version details' link for one of our products on 'WordPress Updates' page, following info is displayed:

An unexpected error occurred. Something may be wrong with WordPress.org or this server’s configuration. If you continue to have problems, please try the support forums.

To don't go too far and invent our Info API, we could simply return custom WP_Error with more friendly message, there are available filters:

• 'plugins_api_result'
• 'themes_api_result'

[meloniq]

There is also an issue when plugin with that same name exists in the wp.org repo, after clicking the "View version history" link, in popup it shows data from the other plugin.