Merge pull request #12 from minexew/master

Fix some things that had been wrong from the beginning
Merge pull request #14 from minexew/master

Fix incorrect simplification of Matrix4f multiplication
Merge pull request #18 from minexew/master

Implement stream-based PNG reading; add class ArrayStream
Added new imports in package modules
Added cast from StreamPos to size_t in pos
Fixed #16
Removed deprecated transform method
Merge pull request #21 from minexew/master

Make Stream-related functions final methods of the respective interfaces
LocalFileSystem implementation (POSIX only)
Add documentation to dlib.filesystem.filesystem
Change 'fileName' to 'filename' as per Phobos convention
Merge branch 'master' of https://github.com/gecko0307/dlib into filesystem
LocalFileSystem implementation (Windows)
Add functions to access global FileSystem
Move PosixFile and PosixDirectory to separate modules
Move WindowsFile and WindowsDirectory to separate modules
Throw away FileIterator in favor of InputRange (POSIX impl.)
Throw away FileIterator in favor of InputRange (Windows impl.)
Add empty property to Queue, LinkedList.
Add "dlib/math/affine_old.d", "dlib/math/matrix_old.d" to excludedSourceFiles as they have the same module name as dlib/math/affine.d and dlib/math/matrix.d.
Use Fibers and lazy evaluation for LocalFileSystem.findFiles