NEW FEATURES:
- introduced SHKFormFieldCellTextLarge, which will replace SHKFormControllerLargeTextField.
- applied to SHKLinkedIn.
- SHKFormController field validation mechanism. Send button is enabled, only if all fields pass validation.
NEW FEATURE: placeholder feature added to SHKFormFieldCellLargeText
NEW FEATURE: LinkedIn posts can now be public or connections-only. Fix for #341
NEW FEATURE: clip with image for large text cell
NEW FEATURE: SHKFormFieldCellTextLarge shows image thumbnail
NEW FEATURES: SHKPlurk made perfect

- got rid of SHKFormControllerLargeTextField
- user can choose qualifier
- user can set private post