Add Emacs support to README

[CsBigDataHub]

Features supported in this Emacs package

• Syntax Highlighting: Comprehensive highlighting for keywords, built-ins, constants, operators, strings, and comments.

• Context-Aware Indentation:

  Smart indentation for braces {}, parentheses (), and brackets [].
  Robust Logic: Correctly ignores braces found inside strings or comments (e.g., x := "{" will not trigger indentation).

• Navigation:

  • Support for beginning-of-defun (C-M-a) and end-of-defun (C-M-e).
  • Works with named functions (func foo()) and variable-assigned anonymous functions (foo := func()).

• Imenu Support: Indexing for top-level functions and variable declarations for quick navigation.

• Electric Support: Integration with electric-indent-mode.