Update NEWS; bump ver. [no ci]

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: oolong
 Title: Create Validation Tests for Automated Content Analysis
-Version: 0.4.4
+Version: 0.5.0
 Authors@R: 
     c(person(given = "Chung-hong", family = "Chan", role = c("aut", "cre"), email = "[email protected]", comment = c(ORCID = "0000-0002-6232-7530")), person(given = "Marius", family = "Sältzer", role = c("aut"), email = "[email protected]", comment = c(ORCID = "0000-0002-8604-4666")))
 Description: Intended to create standard human-in-the-loop validity tests for typical automated content analysis such as topic modeling and dictionary-based methods. This package offers a standard workflow with functions to prepare, administer and evaluate a human-in-the-loop validity test. This package provides functions for validating topic models using word intrusion, topic intrusion (Chang et al. 2009,  <https://papers.nips.cc/paper/3700-reading-tea-leaves-how-humans-interpret-topic-models>) and word set intrusion (Ying et al. 2021) <doi:10.1017/pan.2021.33> tests. This package also provides functions for generating gold-standard data which are useful for validating dictionary-based methods. The default settings of all generated tests match those suggested in Chang et al. (2009) and Song et al. (2020) <doi:10.1080/10584609.2020.1723752>.
@@ -9,7 +9,7 @@ Encoding: UTF-8
 URL: https://github.com/chainsawriot/oolong
 LazyData: true
 Depends:
-    R (>= 3.6)
+    R (>= 4.0)
 Imports: 
     keyATM (>= 0.2.2),
     purrr,

NEWS.md

@@ -1,3 +1,25 @@
+# oolong 0.5.0
+
+* Potential breaking change: the parameter `difficulty` is deprecated. Instead, please use the respective `frewweight` (for STM) and `lambda` (for Warp LDA). For legacy code explicitly using the `difficulty` parameter, this change does not break your code. However, if you use the following pattern, you might need to change your legacy code accordingly.
+
+```r
+## This code is okay
+set.seed(123)
+wsi(abstracts_stm, use_frex_words = TRUE, difficulty = 0.8)
+
+set.seed(123)
+## You will get different results with oolong 0.5.0
+wsi(abstracts_stm, use_frex_words = TRUE)
+
+## You need to explicitly use the old default, which is quite high
+set.seed(123)
+wsi(abstracts_stm, use_frex_words = TRUE, frexweight = 1)
+```
+
+* The package-level documentation is removed.
+
+* Increase the required R version to 4.0 because of `keyATM`
+
 # oolong 0.4.3
 
 * Upgrade Shiny test cases to `shinytest2`