[WIP] Refactoring the build command

[mledoze]

This pull request refactors the build command. It fixes some problems in the code, especially the fact that the class AbstractConverter did too much: the conversion and saving the files to disk.

I also added a factory to create the converters in order to remove the converters variables in the class ExportCommand.

This is a work in progress. Your comments are welcome!

To do:

• [x] add missing translations (see below)
• [x] remove "cym" translations because they are incomplete (only 62 countries have it)
• [x] reorder translations alphabetically
• [ ] fix "suffixes" column in CSV file not being generated as "idd.suffixes"

List of missing translations

• [x] China (CHN): chinese (zho)
• [x] Curaçao (CUW): croatian (hrv), japan (jpn)
• [x] Hong Kong (HKG): chinese (zho)
• [x] Kosovo (UNK): japan (jpn)
• [x] Macau (MAC): chinese (zho)
• [x] Singapore (SGP): chinese (zho)
• [x] Taiwan (TWN): chinese (zho)