Upgrade dictionnaries to upper version

All dictionnaries has a format version number. When a new format version is proposed, it is possible to automatically convert the files to the new version.

We create a term:structure file named dict/01-upgrade.yml with version 1.0:

---
version: '1.0'
my_variable:
  multi: true
my_dyn_family:
  type: "dynamic"
  variable: my_variable
  a_variable:

>>> from rougail import RougailUpgrade, RougailConfig
>>> RougailConfig['main_structural_directories'] = ['dict']
>>> upgrade = RougailUpgrade()
>>> upgrade.load_dictionaries('dict_converted')

The term:structure file named dict_converted/01-upgrade.yml is in version 1.1:

version: '1.1'
my_variable:
  multi: true
my_dyn_family:
  type: dynamic
  a_variable: null
  dynamic:
    type: variable
    variable: my_variable
    propertyerror: false