tools/hash_key library

1. tencent_chat_i18n_tool package
2. documentation
3. tools/hash_key.dart

tencent_chat_i18n_tool package

1. Libraries
2. language_json/strings.g
3. tencent_chat_i18n_tool
4. tools/hash_key
5. tools/i18n_tool
6. tools/utils