Merge pull request #6 from jread-usgs/master

Added Jake Zwart's wedderburn and layer density functions
Added schmidt stability, lakeNumber, layerDensity, and wedderburn number methods with the first revisions after being translated from Matlab.
Merge branch 'master' of github.com:GLEON/Lake-Analyzer-R

Conflicts:
	R/lakeNumber.R
Finished water density manual, changed input parameter names for waterDensity, and removed some weird lines in lakeNumber.
Renamed functions to follow R-like naming convention.
Generated documentation files for all functions. Renamed function files to match function names.
Added documentation outline files.