[cubicweb/doc] Add tutorial on data import in CubicWeb. This involves creating the "tutorials/dataimport" directory structure under "cubicweb/doc" and, inside the "dataimport" directory, putting several files: - a ResT file containing the tutorial *per se*; this tutorial addresses the following issues: * creating a CubicWeb schema for representing a given data set (here, the Diseasome RDF data, for illustration purposes); * parsing the data; * importing the data, by using several stores: + the ``RQLObjectStore``, ``NoHookRQLObjectStore`` and ``SQLGenObjectStore`` from the ``dataimport`` module in CubicWeb; + the ``MassiveObjectStore`` from the ``dataimport`` module in the ``dataio`` cube. The tutorial also provides timing benchmarks of the various stores. - a set of Python files illustrating the data import, in the context of Diseasome RDF data parsing: * a Diseasome RDF data parse module, * a Diseasome data import module, * a CubicWeb schema for representing Diseasome data.

config['rql-cache-size'] = config['rql-cache-size'] * 10

add_entity_type('CWDataImport')

from cubicweb.schema import CONSTRAINTS, guess_rrqlexpr_mainvars
for rqlcstr in rql('Any X,XT,XV WHERE X is CWConstraint, X cstrtype XT, X value XV,'
                   'X cstrtype XT, XT name IN ("RQLUniqueConstraint","RQLConstraint","RQLVocabularyConstraint"),'
                   'NOT X value ~= ";%"').entities():
    expression = rqlcstr.value
    mainvars = guess_rrqlexpr_mainvars(expression)
    yamscstr = CONSTRAINTS[rqlcstr.type](expression, mainvars)
    rqlcstr.cw_set(value=yamscstr.serialize())
    print 'updated', rqlcstr.type, rqlcstr.value.strip()