Merge pull request #17 from dronir/master

Add core tests
Generalized scalar type in scalar binary ops.
Add outer constructors for Vectors

VectorN(a1::T,a2::T,...) will create a typed VectorN{T}.
Add cross() for Vector3
Added barebones matrix types. (No constructors or math yet.)
Merge pull request #19 from jayschwa/cross-product

Cross product
Completed definition of matrix types.
Converted macro to function.
Added some tests of the matrix functionality and squashed some bugs.
Fixed zero for matrices.
Added diag/diagm.
Add (naive) type conversion
Merge pull request #21 from jayschwa/convert

Add (naive) type conversion
Redefined convert in terms of mapBody.
Added convert for matrix types.
Add Travis CI configuration
Make sure to upgrade as well as update
travis: Assume yes when updating
Merge pull request #26 from jayschwa/travis-ci

Travis CI integration
Update README.md