Merge pull request #46 from rennis250/master

bump GLU, GLUT, OpenGL, SDL, and GetC
Add PatternDispatch.jl package
Bump PatternDispatch
Bump Json. 

Bugfix @aviks/JSON.jl#5
Bump PatternDispatch
Bump DataFrames SHA1
Bump DataFrames SHA1
Update Calculus and Optim packages

Added the Calculus package, which contains finite-differencing functions
Updated the Optim package, which depends on the Calculus package
The Optim package now provides trace capabilities
Add Ito.jl package to Metadata
Merge pull request #47 from aviks/topic/Ito

Add Ito.jl package to Metadata
Bump DataFrames SHA1
Added package Rif
Merge pull request #48 from lgautier/master

Rif: An interface to R (embedded R)
Updated Calculus and Optim packages
Bump PatternDispatch
Bump HDF5 sha1
Rif: fix extra trailing newline in Rif/url

This may have been the cause of problems when attempting to install.
Add Compose and Gadfly.
Merge pull request #50 from dcjones/master

Add Compose and Gadfly
Rif: correct SHA1 hash