Update 0000-template.md

Author: seantalts

0000-template.md

@@ -16,7 +16,7 @@ Why are we doing this? What use cases does it support? What is the expected outc
 # Guide-level explanation
 [guide-level-explanation]: #guide-level-explanation
 
-Explain the proposal as if it was already included in the language and you were teaching it to another Stan programmer. That generally means:
+Explain the proposal as if it was already included in the project and you were teaching it to another Stan programmer in the manual. That generally means:
 
 - Introducing new named concepts.
 - Explaining the feature largely in terms of examples.