Impl of Indented should add ?Sized to its constraint

[AstrickHarren]

Here

indenter/src/lib.rs

Lines 183 to 199 in 4574396

	impl<'a, D> Indented<'a, D> {
	/// Sets the format to `Format::Numbered` with the provided index
	pub fn ind(self, ind: usize) -> Self {
	self.with_format(Format::Numbered { ind })
	}
	/// Sets the format to `Format::Uniform` with the provided static string
	pub fn with_str(self, indentation: &'static str) -> Self {
	self.with_format(Format::Uniform { indentation })
	}
	/// Construct an indenter with a user defined format
	pub fn with_format(mut self, format: Format<'a>) -> Self {
	self.format = format;
	self
	}
	}

It will be much helpful if ?Sized is added to as the constraint of the impl so that such a type as D = Box<dyn Write> can take advantage of the use of the methods. One line of code change.

See also #16.