#90 more control of Graphviz dot program logging

[a.hofkamp]

In the log of our project, I have a 1038 warnings from Graphviz dot that look like

Warning:
Graphviz dot warning(s):
Warning: Illegal attribute TOOLTIP in <TD> - ignored
Warning: Illegal attribute TOOLTIP in <TD> - ignored
Warning: Illegal attribute TOOLTIP in <TD> - ignored
in label of node node0

(the above is a short one, on average they are about 15-20 lines each, giving a total of over 15000 lines of log)

I understand that you may want to save such output in a log. It is however not much use to a user to have the log filled with so many of same warnings. I cannot fix them by editing the epydoc.cfg file or by fixing my epydoc doc strings (ie one such warning would give me just as much information).

What's more serious, is the fact that real/useful warnings and errors about doc strings are interleaved with the above flood. As a result, I cannot simply ignore the long list and skip them all by jumping to the last one. I have to check everywhere that there is no 'real' error in between them somewhere.

It would be nice if there would exist a way to get the graphviz warnings out of the way. One solution may be to suppress them (a '--no-graphviz-error-logging' option or a '--no-tooltips' option (in this case)), or clustered together in some way (for example in a seperate file ('--graphviz-log=/dev/null') or at a seperate web-page) so I can simply ignore them without missing any real epydoc errors.