chore: prepare 0.2.1 release

.gitignore

@@ -114,3 +114,4 @@ attic/so_config_old
 /doc/
 /Meta/
 README.html
+revdep/

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: mlr3mbo
 Title: Flexible Bayesian Optimization
-Version: 0.2.0.9000
+Version: 0.2.1
 Authors@R: c(
  person("Lennart", "Schneider", , "[email protected]", role = c("cre", "aut"),
  comment = c(ORCID = "0000-0003-4152-5308")),

NEWS.md

@@ -1,3 +1,24 @@
+# mlr3mbo 0.2.1
+
+* docs: updated some references in vignette.
+* refactor: minor clean up of the internal structure of all loop functions.
+* perf: default initial design constructed based on a Sobol sequence in all loop functions.
+* refactor: no longer depend on `mlr3tuning` but import instead.
+* refactor: `srlrn` sugar function now can construct both a `SurrogateLearner` and
+ `SurrogateLearnerCollection`; dropped `srlrnc`.
+* feat: added `AcqFunctionSD`, `AcqFunctionEHVI` and `AcqFunctionEHVIGH`, introduced
+ `bayesopt_emo` loop function.
+* feat: `AcqFunction`s now include a `$packages` field stating required packages which are checked
+ for whether their namespace can be loaded prior to optimization.
+* fix: fixed bug in `fix_xdt_missing()` helper function.
+* BREAKING CHANGE: renaming `default_loopfun` -> `default_loop_function`,
+ `default_acqfun` -> `default_acqfunction`,
+ `default_acqopt` -> `default_acqoptimizer`.
+* BREAKING CHANGE: `result_function`s now replaced by `ResultAssigner`s.
+* BREAKING CHANGE: renamed `$model` field of all `Surrogate` classes to `$learner`.
+* BREAKING CHANGE: For all `Surrogate` and `AcquisitionFunction` classes fields `*_cols` renamed to
+ `cols_*` (e.g., `x_cols` to `cols_x`) .
+
 # mlr3mbo 0.1.2
 
 * refactor: adapt to mlr3tuning 0.18.0.