Rename package to revealjs.ids

Renames the fork so the IDS corporate design edition can be installed
alongside upstream rstudio/revealjs (same pattern as posterdown.ids).
Use revealjs.ids::revealjs_presentation in the R Markdown yaml header.

Changes: DESCRIPTION (Package name, Version -> 0.9.1.9009, Title notes
the IDS edition), R/utils.R package lookups, skeleton + RStudio
template identity (now 'Reveal.js Presentation (IDS CD theme)'),
README usage, GitLab CI render call, tests, examples. Old documents
referring to revealjs::revealjs_presentation need upstream revealjs
or a search/replace of the prefix.

Change-Id: Id3988b2c3fd348faca3c0951223d0b90c01741dc
diff --git a/inst/rmarkdown/templates/revealjs_presentation/template.yaml b/inst/rmarkdown/templates/revealjs_presentation/template.yaml
index 044aa0b..d88ce65 100644
--- a/inst/rmarkdown/templates/revealjs_presentation/template.yaml
+++ b/inst/rmarkdown/templates/revealjs_presentation/template.yaml
@@ -1,4 +1,4 @@
-name: Reveal.js Presentation (HTML)
+name: Reveal.js Presentation (IDS CD theme)
 description: >
-  Template for HTML presentations based on reveal.js
+  Template for HTML presentations in the IDS Mannheim corporate design (based on reveal.js)
 create_dir: false