Add explicit !!str tag for version field to avoid parsing it as float

Otherwise versions like '0.30' are parsed to float(0.3).
fixes issue #409
Merge pull request #413 from immerrr/patch-1

Add explicit !!str tag for version field to avoid parsing it as float
update changelog
NEW Rename conda to apkg; new "apkg dist" command
Update version
Merge branch 'master' of github.com:algorete/apkg