Merge branch 'ar/043-docs' into 'master'

Docs and prep for 0.4.3

See merge request machine-learning/modkit!245

Author: ArtRand

book/src/SUMMARY.md

@@ -20,7 +20,8 @@
     - [Validate ground truth results](./intro_validate.md)
     - [Calculating methylation entropy](./intro_entropy.md)
     - [Narrow output to specific positions](./intro_include_bed.md)
-    - [Merge multiple bedMethyl files](./intro_bedmethyl_merge.md)
+    - [Manipulate bedMethyl files](./intro_bedmethyl_merge.md)
+    - [Check modified base tags](./intro_modbam_check_tags.md)
 - [Extended subcommand help](./advanced_usage.md)
 - [Troubleshooting](./troubleshooting.md)
 - [Frequently asked questions](./faq.md)