revising validations

The max_limit on the text and history fields is not sufficient for our ocr text files

This is the result of few test samples we tried uploading to dev server

our current max_limit is 10000 in schema of text and 5000 in old / new values in history

Loaded 52.json: 11,305 chars
Loaded 54.json: 25,994 chars
Loaded 14.json: 43,881 chars
Loaded 56.json: 35,409 chars
Loaded 57.json: 18,413 chars
Loaded 23.json: 25,664 chars
Loaded 46.json: 27,068 chars
Loaded 1.json: 25,616 chars
Loaded 35.json: 18,119 chars
Loaded 48.json: 49,759 chars
Loaded 67.json: 31,891 chars
Loaded 16.json: 24,728 chars
Loaded 69.json: 38,884 chars
Loaded 76.json: 9,018 chars
Loaded 50.json: 51,836 chars
Loaded 53.json: 7,300 chars
Loaded 74.json: 51,719 chars
Loaded 33.json: 14,180 chars
Loaded 55.json: 19,703 chars
Loaded 15.json: 16,859 chars
Loaded 5.json: 34,930 chars
Loaded 9.json: 24,928 chars
Loaded 51.json: 5,808 chars
Loaded 10.json: 44,393 chars