Add m2m100 (#10236)

* m2m_100

* no layernorm_embedding

* sinusoidal positional embeddings

* update pos embeddings

* add default config values

* tokenizer

* add conversion script

* fix config

* fix pos embed

* remove _float_tensor

* update tokenizer

* update lang codes

* handle lang codes

* fix pos embeds

* fix spm key

* put embedding weights on device

* remove qa and seq classification heads

* fix convert script

* lang codes pn one line

* fix embeds

* fix tokenizer

* fix tokenizer

* add fast tokenizer

* style

* M2M100MT => M2M100

* fix copyright, style

* tokenizer converter

* vocab file

* remove fast tokenizer

* fix embeds

* fix tokenizer

* fix tests

* add tokenizer tests

* add integration test

* quality

* fix model name

* fix test

* doc

* doc

* fix doc

* add copied from statements

* fix tokenizer tests

* apply review suggestions

* fix urls

* fix shift_tokens_right

* apply review suggestions

* fix

* fix doc

* add lang code to id

* remove unused function

* update checkpoint names

* fix copy

* fix tokenizer

* fix checkpoint names

* fix merge issue

* style

utils/check_repo.py

@@ -30,6 +30,8 @@ PATH_TO_DOC = "docs/source"
 # Being in this list is an exception and should **not** be the rule.
 IGNORE_NON_TESTED = [
     # models to ignore for not tested
+    "M2M100Encoder",  # Building part of bigger (tested) model.
+    "M2M100Decoder",  # Building part of bigger (tested) model.
     "LEDEncoder",  # Building part of bigger (tested) model.
     "LEDDecoder",  # Building part of bigger (tested) model.
     "BartDecoderWrapper",  # Building part of bigger (tested) model.
@@ -75,6 +77,8 @@ TEST_FILES_WITH_NO_COMMON_TESTS = [
 # should **not** be the rule.
 IGNORE_NON_AUTO_CONFIGURED = [
     # models to ignore for model xxx mapping
+    "M2M100Encoder",
+    "M2M100Decoder",
     "LEDEncoder",
     "LEDDecoder",
     "BartDecoder",