Renaming first and last methods to be more intentional and publicising and documenting second.
Adding secondMatching.
Adding secondLast.
Adding secondLastMatching.
Adding third.
Adding thirdMatching.
Adding thirdLast.
Adding thirdLastMatching.
Merge pull request #171 from tobyclemson/first-second-third-last

Renaming first and last variants to better reflect intent and adding corresponding second and third methods.