Cfbs

What's Changed
* Fixed issues found by flake8 by olehermanse in https://github.com/cfengine/cfbs/pull/21
* Fixed issue with undefined functions when adding local files by olehermanse in https://github.com/cfengine/cfbs/pull/22


**Full Changelog**: https://github.com/cfengine/cfbs/compare/0.7.0...0.7.1

What's Changed
* CFE-3762: Added options to specify alternate index by olehermanse in https://github.com/cfengine/cfbs/pull/20


**Full Changelog**: https://github.com/cfengine/cfbs/compare/0.6.2...0.7.0

Fixed issue with escaping special characters in JSON string pretty printing

Added better error message in case of badly formatted JSON.

Files and subdirectories can now be added to the build using relative paths.

Fixed issue with prettifying json in cfbs add command.