v0.7.0

ImagePhantoms v0.7.0

Diff since v0.6.0

Closed issues:

• Need ellipsoid parameters for 3D Shepp Logan (#48)
• Cone Phantom (#57)
• Use Rotations.jl (#59)

Merged pull requests:

• Tweak docs (#54) (@JeffFessler)
• Purge UnitfulRecipes (#55) (@JeffFessler)
• Introduce third rotation angle for 3D objects (#58) (@tknopp)
• Add cone (#62) (@JeffFessler)