devtool: add a 'latest-version' command
This command queries the upstream server for what the latest release is and prints
the output; it is a much neater way to find out these things than fumbling with distrodata,
'bitbake -c checkpkg' and awkward to read csv output in a file.
Examples:
python3 (tarballs):
NOTE: Current version: 3.5.3
NOTE: Latest version: 3.6.3
rpm (git):
NOTE: Current version: 4.13.90
NOTE: Latest version: 4.14.0
NOTE: Latest version's commit:
da3720f62e57648fb1dc2a632744d38866139971
puzzles (git without version tags):
NOTE: Latest commit:
ee8ea9b9785964694cb2b3ad77c3fb2460f49510
Signed-off-by: Alexander Kanavin <alexander.kanavin@linux.intel.com>
