Update RELEASE_NOTES.md
Merge pull request #666 from ovatsus/master

Fixed HTTP decompression throwing AccessViolationException's on Windows Phone
Merge pull request #667 from ovatsus/master

Fixed HTTP decompression throwing AccessViolationException's on Windows Phone (now for profile 7)
Merge pull request #668 from ovatsus/master

Fixed crash on HTTP requests that return 0 bytes
Merge pull request #669 from ovatsus/master

Fixed handling of HTTP response cookies on some corner cases that .NET doesn't natively support
Revert "Fixed handling of HTTP response cookies on some corner cases that .NET doesn't natively support"
Fixed handling of HTTP response cookies on some corner cases that .NET doesn't natively support (this time actually working) (closes #659)