Add the ability to map different input methods and their display labels

[siropkin]

For this, I think can make a configuration, read the input method currently enabled on the system in the settings, and then make a mapping, so that don't have to worry about what to display.

Originally posted by @ZHOUXING1997 in #8 (comment)

The idea comes from that comment ^ - add the ability to map different input methods and their display labels.
For example, on the plugin settings form there will be the ability to add display label mapping to any detected language:

• click add mapping
• detect current language
• add label