distrodata: Take account proxies on distrodata tasks

distrodata: Take account proxies on distrodata tasks

Proxies defined in the enviroment where not taken into account
on the distrodata tasks. This commit implied passing the datastore
into the distro_check library and context manager for the
urllib.urlopen function.

One way to run distrodata tasks is using 'universe' as target and the
'all' distrodata task:

      $ bitbake universe -c distrodataall
      $ bitbake universe -c distro_checkall
      $ bitbake universe -c checklicenseall

Logs are located under TMPDIR/log

[YOCTO #7567]

Signed-off-by: Leonardo Sandoval <leonardo.sandoval.gonzalez@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>