Remove linting exceptions not required any more (and fix blank lines …

…in REAMDE.md)

.markdownlint.yml

@@ -1,24 +1,8 @@
 default: true
 
-# Using h2 has side effects in GitBook's toc. Thus, we sometimes switch from h1 to h3
-MD001: false
-
-MD012:
-  # 2 are required, because GitBook adss two blank lines at the end of a file
-  maximum: 2
-
+# allow arbitrary line length
 MD013: false
 
-# The FAQs state questions - we allow them
-MD026:
-  punctuation: ".,;:!"
-
-# not supported by gitbook
-MD031: false
-
 MD033:
   # we have <a> tags with ids and superscript
   allowed_elements: ['a', 'kbd', 'sup']
-
-# seems to be unsupported by gitbook anymore
-MD045: false

README.md

@@ -100,5 +100,4 @@ For IntelliJ IDEA, just import the project via a Gradle Import by pointing at th
 
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