[GNU ELPA] Rnc-Mode version 0.4

Version 0.4 of package Rnc-Mode has just been released in GNU ELPA.
You can now find it in M-x list-packages RET.

Rnc-Mode describes itself as:

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  Emacs mode to edit Relax-NG Compact files
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More at https://elpa.gnu.org/packages/rnc-mode.html

## Summary:

  Provides mostly indentation, syntax highlighting, and Imenu support.
  Partly based on the info in https://relaxng.org/compact-20021121.html.

## Recent NEWS:

Since 0.3:

- Understands '...' strings.