Modifying Makefile to have `all` target execute tests
Implementing Valuer interface for math/big SQL wrappers

Also adding tests!
Moving nested BigInt and BigRat to non-pointers

To be more consistent with NullTime.
Making nested big.Int/Rat non-pointers

To be more consistent with how the Null types are handling struct
members.
Embedding big.Int/Rat in their corresponding wrappers

Eliminate some of the indirection.
Updating BigInt/BigRat Scan method to handle more types

And added tests.
Moving NullTime to its own file and adding some tests

For Scan and Value.
Adding tests for NullBigInt.Scan()
Updating BigRat.MarshalJSON to marshal the FloatString

Rather than String() which returns a fraction.
Document all the things
Removing old junk from .travis.yml
Updating README to include what the library provides [ci-skip]
Fixing Godoc link in README
Golintifying

And adding gofmt/golint as target in Makefile.
Adding deps to build target in Makefile
Merge pull request #4 from modcloth/implement-valuer-interface

Implement valuer interface