[PATCH] Allow manipulation of htmldoc flags and negation of defaults from trac.ini

[anonymous]

Currently it is possible to set new options (name = value) and replace the values of default options in the trac.ini [pagetopdf] section, but as far as I could tell it was not possible to negate default options (this was annoying because I wanted to use book format, not webpage format), and setting keys with empty string values looks sort of odd. The patch allows the extra values "yes" and "no" to be attached to each key in the [pagetopdf] section. If a value is "yes", the key's value gets set to "None"; if it is "no", the key gets removed from the defaults.

Example:

[pagetopdf]
book = yes
color = yes
numbered = yes
title = yes
webpage = no