mac buildslave produces builds lacking pycrypto

[robk]

so in testing the 'official' mac build - i.e. that produced by the mac buildslave, and found at ​https://dev.allmydata.com/~buildslave/dist/tahoe/mac-10.5/ - both peter and I got (horribly mutilated by wxpython) tracebacks

in short, the build doesn't include pycrypto

if you have an authorized_keys.???? file in ~/.tahoe, then the node will try and create a manhole, which depends on twisted being able to import pycrypto, and explosions rapidly ensue.

removing said file lets the build run (sans manhole)

but the build should be including pycrypto