End of file comment doesn't lex if it is not terminated with a newline

[Tom Hancocks]

If a source code file is terminated by a comment, and that comment is not terminated by a newline, then the lexer will run outside of the bounds of the file and throw and error.

let<Int> foo = 24 // No newline at the end of this comment

There will likely need to be an improvement to character consumption in the lexer to ensure this doesn't occur in other scenarios either.