Added truncation

I added truncation as batch transformation breaks for very rare postings that miss spaces

tokenizer_config.json

@@ -1 +1 @@
-{"do_lower_case": true, "do_basic_tokenize": true, "never_split": null, "unk_token": "[UNK]", "sep_token": "[SEP]", "pad_token": "[PAD]", "cls_token": "[CLS]", "mask_token": "[MASK]", "tokenize_chinese_chars": true, "strip_accents": null, "model_max_length": 512, "special_tokens_map_file": null, "name_or_path": "../models/final/", "padding": true, "tokenizer_class": "DistilBertTokenizer"}
+{"do_lower_case": true, "do_basic_tokenize": true, "never_split": null, "unk_token": "[UNK]", "sep_token": "[SEP]", "pad_token": "[PAD]", "cls_token": "[CLS]", "mask_token": "[MASK]", "tokenize_chinese_chars": true, "strip_accents": null, "model_max_length": 512, "special_tokens_map_file": null, "name_or_path": "../models/final/", "padding": true, "truncation": true, "tokenizer_class": "DistilBertTokenizer"}