Function: write_text_file

--Usage--
> write_text_file(some_string, file: filename)

Write a string to a file in the output directory.
If a file with the given name already exists it is overwritten.

Returns the name of the file written.

This function can only be used in an [[type:export template]], when <tt>create directory</tt> is true.

--Parameters--
! Parameter	Type			Description
| @input@	[[type:string]]		Text to write to the file.
| @file@	[[type:string]]		Name of the file to write to

--Examples--
> write_file("index.html", lots_of_html_code) == "index.html" # index.html now contains the given text

--See also--
| [[fun:write_image_file]]	Write an image file to the output directory.
