Merge pull request #2165 from anandpdoshi/anand-september-9

Fix in web clear cache for Item, cheque printing format
change version in hooks.py
bumped to version 4.3.0
Merge branch 'develop'
Set allow_on_submit for 'page_break', 'letter_head', 'select_print_heading', 'print_heading'. Fixes frappe/erpnext#1810