Fix import warnings when multiGSEA.shiny is loaded

[lianos]

Importing data.table and dplyr cause some "function override" warnings when this package is loaded, or imported from other packages, like so:

Warning messages:
1: replacing previous import ‘data.table::last’ by ‘dplyr::last’ when loading ‘multiGSEA.shiny’ 
2: replacing previous import ‘data.table::first’ by ‘dplyr::first’ when loading ‘multiGSEA.shiny’ 
3: replacing previous import ‘data.table::between’ by ‘dplyr::between’ when loading ‘multiGSEA.shiny’ 
4: replacing previous import ‘dplyr::combine’ by ‘multiGSEA::combine’ when loading ‘multiGSEA.shiny’ 

More judicially importing functions from one of the packages, or use the import/except mojo should do the trick.

import/except

The NAMESPACE file supports syntax like this:

import(PACKAGE, except=c(foo,bar))

And you can get roxygen to do that like so:

#' @rawNamespace import(PACKAGE, except = foo)

Who knew? ... this guy knew ...