*   Improvements and fixes to Docker image.

# Release 0.7.0

## Major Features and Improvements

*   Allow using any installed Cuda >= 7.0 and cuDNN >= R2, and add support for
    cuDNN R4
*   Added a `contrib/` directory for unsupported or experimental features,
    including higher level `layers` module
*   Added an easy way to add and dynamically load user-defined ops