Merge pull request #5 from bcylin/master

Use LKLineActivity as UIActivityCategoryAction
Fix app installation checking
Bump version to 1.3.1
Add few more helpers
Update example with helper usage
Update README with helper examples
Merge pull request #6 from dlackty/helpers

Add helpers
Bump version to 1.4.0
Allow activity with items that contain more objects in addition to images and strings