Make WarningTxt Located in HsModule
AST changes to prepare for API annotations, for #9628
In HsModule, make exports Located and imports not
Add annotations
Capture the end of file position in an annotation
Update for changes in the AST
Change MaybeAnn to AddAnn
Starting on documentation
Create ApiAnnotation module, instead of using Lexer.x
Improve documentation
Add missing note
Note reason for trailing whitespace in test file
Starting to document annotations, need to locate WarningTxt
Add location to WarningTxt