initial commit for DiagrammeR version

[bsgerber]

DiagrammeR branch includes a version that uses the DiagrammeR package to create the consort diagram. Diagrams will consider a variable number of treatment arms and include details to explain exclusion. The numeric values and text labels are somewhat consistent with JAMA style, and will allow for text wrapping.

To create a diagram, the code looks for similar column names in example status tables such as status3 and status4:

make_consort(status3)

It also uses glue and janitor packages similar to other ggconsort functions.