Adding minimal perfect hash function generation.

An implementation of minimal perfect hash function generation as described in
Czech et. al. 1992.  http://bit.ly/137iukS
bump IJulia
bump IJulia
bump IJulia
bump JSON
GoogleCharts: sha1 version bump

surfaceplot fixes
bump UTF16
bump Calendar
bump IJulia
Add HyperLogLog package
Update Units (immutable types)
Merge pull request #351 from nlhepler/devel

ClusterManagers: bump version for a ScyldManager fix
bump IJulia
bump IJulia
bump JSON
GoogleCharts: sha1 version bump

give up on `surfaceplot` and `IJulia`; add parametric plot via a tuple.
Bump Codecs.
Bump Compose/Gadfly.
Patch Grid (break into smaller files; small bugfix)
Bump ProgressMeter