feat(hadithmodel): Add a pre_save for Hadith to set simple text field
feat(hadithmodel): Add a pre_save for Hadith to set simple text field

This si a Django signal which is called before a model is saved. In it,
we set the `simple_text` which is the same as `text field but without
diacritics.

#118

rafidka/hadithhouse,hadithhouse/hadithhouse,hadithhouse/hadithhouse,hadithhouse/hadithhouse,hadithhouse/hadithhouse,rafidka/hadithhouse,hadithhouse/hadithhouse,rafidka/hadithhouse,hadithhouse/hadithhouse,rafidka/hadithhouse,rafidka/hadithhouse,rafidka/hadithhouse