Update ir_qweb.py

Added capital and lower options to the 
<t t-esc="XXXXX" t-esc-options='{"widget": "num2words","case":"upper"}'/> 

<t t-esc="XXXXX" t-esc-options='{"widget": "num2words","case":"lower"}'/> 

<t t-esc="XXXXX" t-esc-options='{"widget": "num2words","case":"capital"}'/>