updated changelog
use locale-independent format specifier for formatting priority values in getHttpAcceptHeader, to avoid problems in locales where a comma is used as decimal separator
Docs appendix RDF formats

- added RDF/PHP specification
- added RDF/JSON specification
added typesAsResources() methods
test for issue 209
PSR-4 + Namespaces
updated dependencies
convert test-helper classes to PHP-5.3+ style
tweak class-names in strings
converted HTTP unit-tests to use namespaces
proper registration of literal-classes
namespaced classes for Format, TypeMapper
Converted Literal unit-tests to use namespaces
merged EasyRdf\Http\Exception
Ported tests for EasyRdf\Sparql
namespaced classes in err-messages
converted more tests
unit-tests for parsers
use ARC from packagist
unit-tests for serialisers