utility-tasks.bbclass: automatic upstream version check
Automatic upstream version check can be triggered by "bitbake xxx -c checkpkg".
The rationale behind is to find a automatic way for version comparison between
current in-use one and upstream progress. The tricky thing is how to find out
useful version string from mass diverse information. Fortunately now it mostly
work for wget based protocol, except some sites (e.g. sourceforge) not providing
a directory service. Repo (git/svn/cvs) based protocols are handled in a very
simple manner, by always tagging as update required. This will be further
improved later. Use 'world' target to retrieve a full version check for all
active recipes.
Along with version check, other package information is also collected from
existing fields in .bb file
