General issues and inconsistencies on bdp-commons

[Piiit]

General issues

• Java package paths are often different. We should have one single main path, ex. it.bz.opendatahub.collectors.......
• Some have (default package), which should never happen
• Some have uppercase package names, that's ugly :-)
• Some have source code encodings set to something different then UTF8
• Some have indentations mixed (spaces and tabs) --> should always be tabs (=4 spaces) maybe we should introduce a .editorconfig file for all our projects
• Most project have no README.md
• There is no main README.md inside data-collectors folder, nor inside the root folder
• We should always use one Framework version (that is, Spring 5.0.10 and 5.0.12 are not OK within the same package)

TODO

• Extend these TODOs (brain storming)
• Create a boilerplate for data collectors
• Fix issues for all data collectors (see above)
• Write FLIGHTRULES.md for data collector contributors