[multi-sources-removal] Drop deleted_entities system table and entities.mtime column
since they were only used by the entities_modified_since api of the
repository which has been dropped. Along with them, the multi-sources-etypes
configuration variable and some sql queries at modification/deletion time of
entities. Bon vent !
Related to #2919300
[MESSAGES CONTROL]
disable-msg = C0301
[VARIABLES]
# Enable / disable this checker
enable-variables = yes
additional-builtins = _, display_name
[BASIC]
required-attributes=
attr-rgx = (w|[a-z_][a-z0-9_]{2,30})
variable-rgx = (w|[a-z_][a-z0-9_]{2,30})$
argument-rgx = (w|[a-z_][a-z0-9_]{2,30})$
[TYPECHECK]
generated-members=debug,info,notice,warning,error,critical,exception