Concepts: Add some architecture documentation

Author: RasmusWL

javascript/ql/lib/semmle/javascript/internal/ConceptsShared.qll

@@ -1,5 +1,13 @@
 /**
- * Provides Concepts which are shared across languages. See `Concepts.qll` for details.
+ * Provides Concepts which are shared across languages.
+ *
+ * Each language will have a language specific `Concepts.qll` file that can import the
+ * shared concepts from this file. A language can either re-export the concept directly,
+ * or can add additional member-predicates that are needed for that language.
+ *
+ * Moving forward, `Concepts.qll` will be the staging ground for brand new concepts from
+ * each language, but we will maintain a discipline of moving those concepts to
+ * `ConceptsShared.qll` ASAP.
  */
 
 private import ConceptsImports

python/ql/lib/semmle/python/internal/ConceptsShared.qll

@@ -1,5 +1,13 @@
 /**
- * Provides Concepts which are shared across languages. See `Concepts.qll` for details.
+ * Provides Concepts which are shared across languages.
+ *
+ * Each language will have a language specific `Concepts.qll` file that can import the
+ * shared concepts from this file. A language can either re-export the concept directly,
+ * or can add additional member-predicates that are needed for that language.
+ *
+ * Moving forward, `Concepts.qll` will be the staging ground for brand new concepts from
+ * each language, but we will maintain a discipline of moving those concepts to
+ * `ConceptsShared.qll` ASAP.
  */
 
 private import ConceptsImports

ruby/ql/lib/codeql/ruby/internal/ConceptsShared.qll

@@ -1,5 +1,13 @@
 /**
- * Provides Concepts which are shared across languages. See `Concepts.qll` for details.
+ * Provides Concepts which are shared across languages.
+ *
+ * Each language will have a language specific `Concepts.qll` file that can import the
+ * shared concepts from this file. A language can either re-export the concept directly,
+ * or can add additional member-predicates that are needed for that language.
+ *
+ * Moving forward, `Concepts.qll` will be the staging ground for brand new concepts from
+ * each language, but we will maintain a discipline of moving those concepts to
+ * `ConceptsShared.qll` ASAP.
  */
 
 private import ConceptsImports