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* Adding support for degrotesquing markdown files (contents of code and quotes are kept)
* Added support for processing plain text files; The distinction whether a file is a plain text file or a HTML/XML derivative is done using the extension (see Appendix B for used extensions) and by evaluating the contents; Everything is replaced in text files. When processing a file as a XML/HTML derivative, elements are skipped. Introducing the options __--text__ / __-T__, __--markdown__ / __-M__, and __--html__ / __-H__ to explicitly set the file type.
* Supporting different target encodings for the replacements using the __--format / -f _<FORMAT>___ option (the option __--unicode__ / __-u__ was removed):
* &8216;__unicode__&8217;: uses numeric entities (e.g. &8216;&8211;&8217; for an &8216;—&8217;);
* &8216;__html__&8217;: uses numeric entities (e.g. &8216;&mdash;&8217; for an &8216;—&8217;);
* &8216;__text__&8217;: uses plain (utf-8) characters (e.g. &8216;—&8217; for an &8216;—&8217;).
* 100 % test coverage :-)
* renamed master branch to main