[IMP] Add and improve filter tooltips of sales module.

Respected Sir,
I have add and improve existing filter tooltips in following file of sales module.
	modified:   addons/account/account_view.xml
	modified:   addons/crm/crm_lead_view.xml
	modified:   addons/crm/crm_phonecall_view.xml
	modified:   addons/crm_claim/crm_claim_view.xml
	modified:   addons/crm_partner_assign/crm_lead_view.xml
	modified:   addons/email_template/res_partner_view.xml
	modified:   addons/mrp/mrp_view.xml
	modified:   addons/sale/sale_view.xml
	modified:   addons/sale_layout/views/sale_layout_category_view.xml
	modified:   addons/stock/product_view.xml