miscellaneous book db query functions

[ansarimofid]

Following functions should be created in class.books.php

• fetch_book_data()

Returns array containing the record of whole books_table

• author_count()

Returns no. of distinct authors

• getJsonData(phpObject or array)

parses php object or array into json data

[ansarimofid]

reduced one function

[vermanil]

fetch_book_data() and book_list()[is present] wiil be same after implementing fetch_book_data()