tensorr 0.1.1

• added dimnames to tensors (#7)
• fixed bug when extracting indices using negative or repeated indices (#8)
• lower required R version to 3.3.0 (#10)

tensorr 0.1

• Added initial sptensor and dtensor objects.
• Implemented extract and replace operations for tensors.
• Implemented conversion functions between dense and sparse formats.
• Implemented group generics for tensors.
• Implemented tesnsor operations such as unfolding and tensor multiplication.
• Added a NEWS.md file to track changes to the package.