CLI 2.0 (Better support for other formats; iOS, Android, Flutter, PHP .po, C/C++ .po, etc.)

[JanCizmar]

Recently, we released support for many more formats like iOS, Android, Flutter, PHP .po, C/C++ .po. To Tolgee more convenient to use with this new features, we need to enhance the CLI.

• [x] Make everything configurable via .tolgeerc
  • so we can detect this file in GitHub/GitLab apps later
  • so the same export/import configuration can be shared by all the project users
  • [x] Enable configuration of other relevant fields from export/import properties
  • [x] Enable specifying files as a source to push
    • [ ] Files to push can be mapped to specific language tags in platform
    • [x] Specific files can be ignored
    • [x] Unused keys can be marked with specified tags
    • [ ] Unused keys can be removed (https://github.com/tolgee/tolgee-cli/issues/18)
    • [x] Enable specifying of desired message format
  • [x] Enable specifying languages to pull
    • [x] Languages can be mapped to files
    • [x] Specific language can be ignored
    • [x] Only keys with specified tags are included
    • [x] Keys with specified tags are excluded
    • [x] Only translations in specified state are included
• [x] Option to not to delete destination folder completely
• [ ] Make tolgee login done via browser, so it's easier to create the API key
• [x] Use single-step import, so the import is done in single request
• [x] Option to remove keys not contained in source (pushed) file