Use list of allowed transforms

[petermr]

• Enumerate the allowed transforms in norma.
• Check that input argument (e.g. foo in --transform foo) is allowed
• provide default input and output files for each transform

[petermr]

have created Type in NormaTransformer.

    public enum Type {
        HTMLUNIT("htmlunit", null, CTree.FULLTEXT_HTML, null, CTree.FULLTEXT_XHTML),
        JSOUP("jsoup", null, CTree.FULLTEXT_HTML, null, CTree.FULLTEXT_XHTML),
        TIDY("tidy", null, CTree.FULLTEXT_HTML, null, CTree.FULLTEXT_XHTML),

        HOCR2SVG("hocr2svg", "image/", CTree.PNG, "svg/", CTree.SVG),
        CSV2HTML("csv2html", "table/", CTree.CSV, "table/", CTree.HTML),
        PDF2HTML("pdf2html", null, CTree.PDF, null, CTree.HTML),
        PDF2IMAGES("pdf2images", null, CTree.PDF, "image/", CTree.PNG),
        PDF2SVG("pdf2svg", null, CTree.PDF, "svg/", CTree.SVG),
        PDF2TXT("pdf2txt", null, CTree.PDF, null, CTree.TXT),
        TEX2HTML("tex2html", null, CTree.TEX, null, CTree.HTML),
        TXT2HTML("txt2html", null, CTree.TXT, null, CTree.HTML);

        public String inputFilename;
        public String outputFilename;
        public String transform;
        public String inputDirName;
        public String outputDirName;

        private Type(String transform, String inputDir, String inputFilename, String outputDir, String outputFilename) {
//
        }

Thus CSV2HTML is:

        CSV2HTML("csv2html", "table/", CTree.CSV, "table/", CTree.HTML),

which gives parameter, default inputDir, input suffix, default outputDir, outputSuffix.

This allows default for directory names

[petermr]

Discussed at length with @tarrow ...

Agreed to redesign as:

--transform type param/s

where type is (say) any of the examples above (csv2html)...
Historically

--transform foo.xsl

was shorthand for

--transform xml2html foo.xsl

so let's make it explicit and deprecate the type-less command