[R6RS] Boolean or boolean

[Anton van Straaten]

> Please respond with your votes on the following two questions:
> 
>   1. should we capitalize boolean as ticket 216 suggests?

No.  It shouldn't be capitalized in the code (see below), therefore it 
shouldn't be capitalized in the text.

However, there should probably be a footnote to explain the usage and 
avoid dissing George.

>   2. if we do capitalize boolean, should we rename boolean? to Boolean?

No.  That would be an incursion of natural language rules into code, up 
with which we should not put.

Anton