[nemo-qml-plugin-contacts] Do not change filter type for required property

Although the required property casues the results to be filtered, we
should only switch between FilterNone and FilterAll modes due to changes
to the filter pattern.
Fix test data
[nemo-qml-plugin-contacts] contactcache now exports internal ID lists
Remove obsolete function declaration
Merge pull request #55 from matthewvogt/jb9408

Do not change effective filter type for requiredProperty changes
Update dependency versions
[nemo-qml-plugin-contacts] Do not reimport existing contacts

For any imported contact with a GUID value, ensure that GUID is not
already present before import.
Merge pull request #56 from matthewvogt/import-stability

[nemo-qml-plugin-contacts] Do not reimport existing contacts
[qmldir] Add Module Identifier Directive
[nemo-qml-plugin-contacts] Fix tst_seasideperson
Merge pull request #58 from matthewvogt/auto-test

[nemo-qml-plugin-contacts] Fix tst_seasideperson
Merge pull request #57 from thp/module-identifier-directive

[qmldir] Add Module Identifier Directive
[nemo-qml-plugin-contacts] Contact search should match despite diacritics

When a contact's details contain diacritics, they should be ignored for
searching purposes.  If the search string contains diacritics, however,
they should be matched by the contact details.
[nemo-qml-plugin-contacts] Only match searches against local part of addresses

The domain of an address is unlikely to be relevant to matching a
specific person.
Merge pull request #60 from matthewvogt/search

[nemo-qml-plugin-contacts] Contact search should match despite diacritics
Fix emission of dataChanged signal
[nemo-qml-plugin-contacts] Add accessor function for multiple avatar URLs
Merge pull request #61 from matthewvogt/fix-data-changed

Fix emission of dataChanged signal
Merge pull request #59 from matthewvogt/preferred-avatar

[nemo-qml-plugin-contacts] Add accessor function for multiple avatar URLs