Detect licenses during init

[loleg]

In the init process described in #63 there could be a detection of a LICENSE or LICENSE.md file in the current folder, leading to the addition to datapackage.json of the appropriate license fields from the specification. A range of open data licenses could be supported, perhaps linked to opendefinition.org to stay up to date.

See also: detectable licenses on GitHub.com

[anuveyatsu]

@loleg you can add ODC licenses during the init command now (available from v0.9.0). By default, "ODC-PDDL" license is added but you can run the command in the interactive mode using -i option and select another license. Do you think it addresses this issue?

[loleg]

@anuveyatsu I don't think this completely responds to the suggestion, since I was thinking the license could be automatically detected. But for most intents and purposes, I think this will do the job.

Is there a confirmation of the default license being added?