[sortable] migrate tests and listener

* edbfc92 [sortable] add mongodb odm support
* 7cd50f2 [sortable] do not allow nullable position field
* 238b6bb [sortable] support multiple sortable fields
* df764dc [sortable] refactor to support more positions per object
* bcd0ee2 [tests] add sortable mapping tests
[sluggable] begin to refactor, remove handlers for now
[sluggable] migrate listener and tests
Refactor handling basenames of files
[uploadable] migrate uploadable tests and listener
[loggable] migrate listener and tests
[tree] migrate listener and tests
[mapping] start to refactor mapping extension
[tree] update based on mapping changes
[translatable] update mapping and tests
[loggable] update mapping
[tests] move under Gedmo namespace
[tests] some updates related to postgresql support
[tests] adapt as possible to postgresql
[tree] php5.3 support
[uploadable] migrate mapping and tests
[tree] FIX level in MaterializedPath if 'path_starts_with_separator' or 'path_ends_with_separator' are set
adjustments after rebase
[sluggable] allow to slug identifiers
[tests] install phpunit through composer