Merge pull request #497 from ezsystems/search-filter-refactoring

Search filter refactoring
EZP-21438: handle view_embed permission in XMLText converter
EZP-21438: update tests
Fixed criteria construction

Solr tests are not skipped any more, but run correctly.
Throw exception on invalid header name
Set content type header correctly
Added mandatory version field to schema
Fixed: test dependencies
EZP-21909: enable indexing Content states
EZP-21909: use MultipleIdentifierField to index Content states
EZP-21909: addded SetContentState Solr slot
EZP-21909: fixed: set default states for copied Content
Updated: reuse ContentState assertions
Fixed string
Escape slashes in subtree query

TODO: Provide sane general escaping in Solr strings?
Try to configure Travis to run tests with different Solr versions
Added new test case for EZP21906 - Search API returns wrong number of total objects with content having multiple locations
Merge pull request #604 from ezsystems/fix-EZP-21909-copy-content-with-object-states

Fix EZP-21909: ObjectStates are not set for copied Content
Merge pull request #648 from pedroresende/EZP-21906

Added new test case for EZP21906 - Search API returns wrong number of total objects with content having multiple locations
Fixed build matrix in Travis config