Wysiwyg: split node/mark addition into separate methods in extension builder

[d3m1d0v]

At the current moment ExtensionBuilder has two methods to declare new nodes and marks:

// for nodes
builder.addNode();

// for marks
builder.addMark();

In each method you should provide:

• prosemirror schema spec
• markdown parser spec
• markdown serializer spec
• custom view for entity (optional)

This is inconvenient for several reasons:

• impossible to separate declaration for prosemirror from declaration for markdown parsing and serializing
• sometimes it is required to parse different markdown-tokens into one prosemirror-node (for example, parse code_block and fence tokens to code_block-node in prosemirror). In this case you should add empty schema spec and empty serializer spec into builder.addNode()

Proposal

Split builder.addNode() and builder.addMark() into separate methods:

builder.addNodeSpec();
builder.addMarkSpec();
builder.addParserSpec();
builder.addSerializerSpec();
builder.addNodeView();
builder.addMarkView();

And refactor code in CodeBlockSpecs extension