riot 1.0.0

In this first major release, we: * Added support to read MRtrix .tck/.tsf file formats (#5). * Added support to read TrackVis .trk file formats (#5). * Use only one core to compile VTK for compliance with CRAN policy (thanks to Prof. B. Ripley). * Added tilde expansion on file paths.

We make it the first major release as we consider that the most popular tractography formats are now supported by riot. We chose by design to support only VTK and medInria file formats for writing.

riot 0.0.1