* initial dataframe commit
* initial dataframe port of core app
* rename variables for clarity
* remove unused import
* comment out unused code
* fix array handling bug in crossfilter dimension creation
* allow creation of empty dataframes
* handle non-existent columns
* handle non-existent columns
* revise tests for new dataframe
* comments for clarity
* comments for clarity
* generate bulk add placeholder with real gene names
* fix bug in gene name adding
* more dataframe unit tests
* fix bug - subset from current world, not universe
* put cut and pasted code into a single function
* improve caching of crossfilter
* remove cascading update bug from graph
* more performance work
* improve state handling for scatterplot
* performance optimization of critical path
* add column summarization
* dataframe utils
* add callOnceLazy
* fix tests
* minor updates found during review
* fix misspelling
* remove RESTv02 from function names
* comment cleanup
* cut/icut col parameter defaults to null
* break up large test
* improve tests and comments on dataframe at/has functions
* add Dataframe withCol/dropCol
* expression varData now stored in a dataframe
* dead code cleanup
* use dataframe.summarize()
* test cases for Dataframe.col.summarize
* update test cases for new dataframe summarize
* improve naming
* use new hasCol API
* add comments
* add more Dataframe.withCol tests
* add ability to specify row index in cut operation
* retire subsetVarData function
* correctly handle expression subsetting
* lint and improve comments
* rename cut to subset
* changes based on PR review
* initial dataframe commit
* initial dataframe port of core app
* rename variables for clarity
* remove unused import
* comment out unused code
* fix array handling bug in crossfilter dimension creation
* allow creation of empty dataframes
* handle non-existent columns
* handle non-existent columns
* revise tests for new dataframe
* comments for clarity
* comments for clarity
* generate bulk add placeholder with real gene names
* fix bug in gene name adding
* more dataframe unit tests
* fix bug - subset from current world, not universe
* put cut and pasted code into a single function
* improve caching of crossfilter
* remove cascading update bug from graph
* more performance work
* improve state handling for scatterplot
* performance optimization of critical path
* add column summarization
* dataframe utils
* add callOnceLazy
* fix tests
* minor updates found during review
* fix misspelling
* remove RESTv02 from function names
* comment cleanup
* cut/icut col parameter defaults to null
* break up large test
* improve tests and comments on dataframe at/has functions
