Provides support for formatting key sequences.

## Package Specification

This is a collection fo various formatters for key sequences. The formatters are accessible through the `KeyFormatterFactory`. To change how keys are formatted in the user interface, call `KeyFormatterFactory.setDefault(IKeyFormatter)`. They provided formatters are:

FormalKeyFormatter
  Provides a formal grammar for reading and writing key sequences.
NativeKeyFormatter
  Provide a native-looking, human-readable format for keys.
CompactKeyFormatter
  A variation of the native formatter that provides a more compact representation.
EmacsKeyFormatter
  An Xemacs-style formatter (e.g., C^x C^x).