Added a utility method to get an array of architecture names for
a given executable.
This will be useful for, say, figuring out what Python was compiled for,
to know what to compile a C-based module as.
Signed Off By: Max Howell <max@methylblue.com>
I added a test and made the function use `which` if the path provided is not
absolute. I considered allowing relative paths, but then it is possible for
the function to take eg. the svn binary from the current directory when you
meant the one in the path, and that could be a confusing bug.
981dba1b35