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/tests/testthat/test-utils.R b/tests/testthat/test-utils.R
index 98ec1d0..56e95a4 100644
--- a/tests/testthat/test-utils.R
+++ b/tests/testthat/test-utils.R
@@ -35,7 +35,7 @@
 })
 
 test_that("revealjs lib path is found in package", {
-  expect_match(revealjs_lib_path(), "revealjs/(inst/)?reveal\\.js-")
+  expect_match(revealjs_lib_path(), "revealjs(\\.ids)?/(inst/)?reveal\\.js-")
   expect_true(dir.exists(revealjs_lib_path()))
 })