Add travis build configuration

This requires a custom install of g++-4.8, but it works.
Change algorithms to be class-based

This makes algorithm configuration a bit more sensible, instead of
having to pass in a bunch of parameters (possibly with defaults) to a
single function.

Fixes #5.
Modify a player rating map inplace

Algorithms returning by value is a bit ineffecient, especially for large
data sets (RRI?). This patch is the start of converting algorithms to
generally modify a rating map in place.
Pass a SpPlayerRatingMap to SplitPlayersGreedy

Since we updated our player rating algoritm to return a map instead of a
set, this function should take that as an input.
Add DatedGame

This class adds a date to a game.

Fixes #8.
Make Game's boost::noncopyable private
Pass shared pointers by ref to const

Also delete Game.cpp, it can be all header.
Add get_{winning|losing}_score

This is needed in RRI calculations.
Update game to use unsigned int for scores
Change SpTeamPair to SpTwoTeams (array)

Can't iterate over a pair, and pairs are intended for mixed types,
generally.
Add weeks_after

This utility calculates the number of weeks later one date is than
another. This calculation isn't a pure date subtraction, since we first
rewind the earlier date to the start of the week (Monday), *then*
calculate the weeks afterwards.

We don't do fancy math, we actually iterate over the weeks and count, so
this might not (probably isn't) the best implementation. However, it's
hopefully correct, withtout worrying about Weird Date Stuff.
Use gregorian, not gregorian_types

In the event of an error, the date is used for IO, which fails w/o the
full include.
Add DatedGame typedefs to include/flatball/Common
Add team accessor to Game
Add documentation

This includes configuration for `make docs` as well as inline
documentation for classes.
RatePlayersBasic needs to inherit from RatePlayers

Before, the base class wasn't doing anything.
Fix typo: FLATBAL_ to FLATBALL_
Add base algorithm template class

This base class has both an inplace and copy versions, which can be used
as superclasses of algorithms.
Add TODO
Fix bad placement of documentation