Adds XSSF conditional formatting (#15429)

- adds server-side formatting parsing for both types, extendible
- adds style holder map in state
- HSSF parsing present but disabled (errors in POI API regarding formula
reading)
- adds maven dependency necessary for XSSF formula color parsing

Change-Id: I6a254a2a09d7bcbac419cc85444a5f18858ddb63