Removed spec.dataframe option. Instead returns dataframe invisibly.
Replaced paste with paste0 (speed and compactness of code)
Added spaces after commas and operators
Added .Rproj.user to .gitignore
Corrected name of output variable to output.data.frame
Removed asterisks from errors and warnings.
Added a new parameter, image, which determines whether plot images will be produced. It defaults to FALSE.
Removed .Rhistory file from R/
Merged serbinsh/master with master

Merge remote-tracking branch 'serbinsh/master'

Conflicts:
	.gitignore
Merge pull request #5 from sebastian-c/master

Option to not produce images