According to #141 re-add shared phonebook group:

Make contacts in shared groups (based on visibility level other than "Me only")
visible, searchable and exportable by other users,
Make contacts able to be free of group.
+ small fix on send sms page : save selection if focus is lost
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* Users can now share their contacts by changing group visibility level.
If user selects "Members" or "Anyone" for a group and select that group for a contact, then all other users can see this shared contact and group name on phonebook page and search results on send sms page.

* Users can create or import contacts without need to create any groups for it,
contact may belong to no group, may belong to one group or many groups.

* When user types number in destination select box and clicks outside, input does not dissapearing anymore. This small fix does not affect search script.

All changes was tested in a test environment with php 5.3 and MySQL backend.
This request is to implement accepted feature #141