DOC: Update authors, changelog

[effigies]

Ran through the first few steps of http://nipy.org/nibabel/devel/make_release.html

Can be merged as-is or I can update as we get closer to release.

[codecov-io]

Codecov Report

Merging #515 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #515   +/-   ##
=======================================
  Coverage   94.14%   94.14%           
=======================================
  Files         175      175           
  Lines       23882    23882           
  Branches     2568     2568           
=======================================
  Hits        22484    22484           
  Misses        918      918           
  Partials      480      480

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[coveralls]

Coverage remained the same at 96.156% when pulling bc29cad on effigies:pre_release into 19fd3f8 on nipy:master.

[coveralls]

Coverage remained the same at 96.156% when pulling 178a2e4 on effigies:pre_release into 19fd3f8 on nipy:master.

[matthew-brett]

Thanks for doing that - let's merge and do new PRs as we need to.