Include callhistory only in Tizen mobile target.

BUG=XWALK-1837
Bump version to 0.68
Merge pull request #323 from zolkis/master

Fix XWALK-1837: include callhistory only in Tizen mobile target
[Phone] Added IVI Phone support

This extension implements the phone interfaces for IVI using phoned.
It replaces the existing wrt-plugins-ivi-hfp used by Modello home screen.

Original wrt plugin
https://review.tizen.org/git/?p=profile/ivi/wrt-plugins-ivi-hfp.git

It implements the following api:

- selectRemoteDevice()
- unselectRemoteDevice()
- getSelectedRemoteDevice()
- invokeCall()
- answerCall()
- hangupCall()
- activeCall()
- muteCall()
- getContacts()
- getCallHistory()
- addRemoteDeviceSelectedListener()
- removeRemoteDeviceSelectedListener()
- addCallChangedListener()
- removeCallChangedListener()
- addCallHistoryEntryAddedListener()
- removeCallHistoryEntryAddedListener()
- addCallHistoryChangedListener()
- removeCallHistoryChangedListener()
- addContactsChangedListener()
- removeContactsChangedListener()

BUG=XWALK-1661

Signed-off-by: Jimmy Huang <jimmy.huang@intel.com>