finish move of php / python meterpreters to metasploit-payloads

[bcook-r7]

This PR updates metasploit-payloads to 1.0.10, which no longer blacklists php and python meterpreter, deletes the copies from data/meterpreter and adjusts the stages to read from the gem instead.

Verification steps

• Ensure that Python meterpreter still works, e.g. minimally run something like this:

./msfconsole -qx 'use exploit/multi/handler; set payload python/meterpreter/reverse_tcp; set lhost 192.168.56.1; run'

and connecting to port 4444 should spit out the payload

• Ensure that PHP meterpreter still works, same as above.

[bcook-r7]

This should be good to go (and I need it merged to move forward with more payload updates).