New transforms, CiceroEdit for migration, Tests revisions and Bug fixes

[jeromesimeon]

Changes

• Fixes async bug in markdown-transform
• Adds --via option to CLI, allowing to specify intermediate steps in the transform
• Slate DOM changes:
  • clause node now include the elementType field
  • clause node only have a src field when available
  • variable nodes can also have an identifiedBy field
  • formula nodes now include dependencies and source code
• Changes to the transform:
  • revert changes to commonmark format with wrapped variables so it is consistent with the last markdown-transform release
  • new ciceroedit with import to ciceromark which is based on the previous commonmark -> ciceromark transform. Kept around only for migration.
  • distinguishes between ciceromark and ciceromark_untyped the latter is used for ciceroedit transform.
  • commonmark -> ciceromark transform now only identifies clause nodes
  • ciceromark -> commonmark transform does not create wrap variables anymore. Remove corresponding duplicate code from markdown-template package.
• Testing:
  • Completely revised to adjust to the new transforms. Prior tests from markdown to slate/html etc are not in the markdown-transform package.
  • CommonMark tests are split in separate files (for ciceromark, ciceroedit and the spec)

[coveralls]

Coverage decreased (-1.2%) to 89.709% when pulling 92f89fa on parserv2 into 45d0552 on master.