[multi-sources-removal] Turn ConnectionsSet into simpler ConnectionWrapper
also, SqliteConnectionWrapper becomes a subclass. This is allowed since
now ConnectionsSet responsability has been reduced to handling the system
source only.
This changeset also:
* drops useless cnxset_set / check_connection api
* deprecates former .source / .connection / container api
but it renames neither the session's cnxset attribute, nor the related
repository method.
Related to #2919300
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()