* enforce column name uniqueness for obs and var
* parameterize the column name containing obs and var user-readable names
* use the new annotation index value from schema
* update f/e unit tests
* PR review suggestions
* lint
* 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
* first flatbuffer schema
* do not lint auto-generated files
* add flatbuffers package
* add flatbuffer module
* wire up /data/X/T route
* use flatbuffers for matrix data fetc
* clarity and comments
* add flatbuffer layout route
* clean up obsolete code
* fix tests
* move flake8 config to setup.cfg
* add comments
* lint
* rework layout routes for fbs
* add more type support to fbs
* lint
* add flatbuffer support for annotations
* function name improvements
* fix botched merge with master
* remove unused import
* route cleanup for flatbuffers
* rename function for clarity
* add missing globals to Jest tests
* fix client JS tests
* fix routes for Python tests
* comments for clarity
* non-finite floating point hardening
* more non-finite number handling
* lint
* fix tests for summarizeAnnotations
* harden diffexp calculation against FP errors
* cleanup unused code
* lint
* add encoding tests for flatbuffers
* application type specified as strings
* fix spelling error
* improve variable names
* add note about documentation gap
* rename FBS DataFrame to Matrix
First cut at test for stateManager/world. Test data for REST responses factored out into separate file for shared use by Universe and World tests. Also cleaned up some debugging code.