[oe] Bitbake task logging

[Aeschbacher, Fabrice]

> > e) I'm not 100% on this yet but I'm wondering if we should scrap
> > stdout/stderr output to the UI console in debug mode, just 
> make it clear
> > where the output went on the console? If you ever have two 
> tasks running
> > the output is unreadable anyway.
> 
> Yes, stdout/stderr from two (or more) concurrent tasks are pretty
> unreadable at best.  But it could make sense to have a debug mode which
> does output stdout/stderr to console, while disabling concurrent task
> execution.
> 
> /Esben

For now, oe_note() outputs in the logfile, which is quite far away from where bitbake is invoked - moreover, in a directory which gets deleted at every 'bitbake -c clean'

It would be really nice to make it possible (which is very frequent when debugging a recipe) to just write debug output to the console. 

Fabrice Aeschbacher