20200210 - v2.2.9

new terminal mode options: -safe, -listed=0 and -reuse:

• -safe=1: use a temporary script to pass arguments, this is the most accurate way for argument passing.
• -listed=0: set nobuflisted for the terminal buffer.
• -reuse: when using -mode=term and -pos=tab together, try to use a reusable terminal tab.

All of these are for -mode=term only.