Add 'hook' parameter to item create/update/delete methods
File downloads using static method is deprecated. Only download files after a PodioFile object is present
Rename lib/PodioAPI.php to lib/Podio.php so people won't include the wrong one
Include more information in exceptions
Add 'hook' option for other methods that support it
Typo
Automatically set the type property when manually creating a new ItemField
Only start session if it hasn't already been started. Fixes #19
Fix bad URL
Add PodioTag::get_for_app(). Fixes #13
Clarification
Merge pull request #17 from Antronin/master

Adding PodioForm feature
Fix PodioForm. Fixes #16
form_id is an id property
Add PodioWidget
Add convenience methods for adding and removing fields on items and apps.
Make it possible to pass PodioEmbed object directly to PodioEmbedItemField->set_value(). If it feels right the same should be done for Contact, App, Image, Video and File fields.
Files can be blank
Fix horribly wrong example
Make it possible to pass in PodioContact, PodioFile and PodioItem when using set_value on the appropriate fields