Brainload

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- Added support for loading affine transformation matrices, e.g., files or mri_info output that follows the FreeSurfer register.dat format.
- New group-level functions for loading stats data
- Support for parsing talairach.xfm files
- Add brainlocator class that allows to conveniently find the vertex in a surface file that is closest to some RAS coordinate.
- Add BrainVoxLocator class that allows to conveniently find the segmentation label of a voxel. Also supports finding the label of the closest voxel with non-empty (not 'Unknown') label and gives the distance to it.
- Add support for loading m3z files, like mri/transforms/talairach.m3z

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- Added support for exporting meshes to formats used by standard 3D modeling software like Blender in formats OBJ (Wavefront object) and Stanford PLY.
- Improve some doc strings
- Add more unit tests

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- Added support for loading FreeSurfer annotation files. This allows one to load cortical parcellation information from an Atlas, e.g., from the Desikan atlas from the '?h.aparc.annot' files. An annotation consists of several groups of vertices, each of which is assigned a label and a color.
- Added support for loading FreeSurfer label files. This allows one to load sets of vertices assigned to a group, e.g., the list of all vertices which belong to the cortex from the files '?h.cortex.label'.
- Add support for masking data using an arbitrary mask, i.e., set the data values to NaN at a list of indices. Typically this is used to mask out the medial wall in brain morphometry data. You can use any data, e.g., a loaded label, to build the mask.

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- Added support for Python 3. We now test for Python 2.7, Python 3.5 and Python 3.6 on Travis CI.
- Renamed all occurrences of the word morphology to morphometry, including in meta data entries and function names. This breaks compatibility with v0.2.0.
- Extend documentation: add workflow examples. The documentation is no longer only API documentation.
- Add recipe for anaconda build.

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- First official version.
- Added API methods for loading group data.
- Renamed spatial_transform module to spatial. This breaks compatibility with previous versions.
- Added methods for checking for files in subject directories in nitools module.