fix Armitage decompressing path in comments

Edit:
msf_install.sh
- Line 51: "/opt/armitage" --> "/usr/local/share/armitage"
- Line 448: "/opt/armitage" --> "/usr/local/share/armitage"

update_armitage.sh
- Line 31: "/opt/armitage" --> "/usr/local/share/armitage"
- Line 67: "/opt/armitage" --> "/usr/local/share/armitage"