Edit PR nits

docs/UserGuide.md

@@ -182,10 +182,9 @@ The quick reference is meant for **fast and reliable** lookup of commands and th
 
 Sets the course code in question. 
 
-Format: `setcrs COURSE_code`
+Format: `setcrs COURSE_CODE`
 
-Duplicate course are not allowed.
-Courses are case-insensitive.
+Course codes are case-insensitive.
 Course code should follow the format "XX1234Y", Y is optional.
 
 <markdown class="d-print-none">---</markdown>
@@ -200,7 +199,7 @@ Format: `addstu n/NAME nn/NUSNET [p/PHONE] [e/EMAIL] [m/MAJOR] [t/TAG]…​`
 * Add a student with the given details.
 * The name and nusnet id must be provided. And nusnet id must be unique.
 * All the remaining fields are optional. If not provided, a placeholder value will be used.
-* Name cannot be empty or spaces only, contain only alphabets and cannot have double spaces 
+* Name cannot be empty or spaces only, contain only alphabets and cannot have double spaces. 
 
 <box type="tip" seamless>