Documentation: report options description place

[Dmitry Pavlov]

Hello,
I'm working on help documentation for budget report as an addition to my
improvements <https://github.com/Gnucash/gnucash/pull/2> for it. Currently
there is no description neither in help nor in tutorial, so I want to add
it and describe this report specific options -- what do they do and how
they affect report.
I found the place to put report description (help_ch_reports.xml), but I
doubt if it's a good place to put detailed information about options, right
after the main text. May be there is some better place?
Current format of options description is a list of "option name --- what
does this option do" elements

BTW, do you accept document changes as pull requests on github?

-- 
Best regards,
Dmitry Pavlov