Call execve from fork_and_exec in sys/redox.rs so they can share code
Created by: blackle
Problem: execve and fork_and_exec share a large chunk of code
Solution: Remove the argument building and path resolution in fork_and_exec and call execve instead
Changes introduced by this pull request:
- There is no more repeated code between fork_and_exec and execve
Drawbacks: Ion forks even if the file doesn't exist, whereas before it wouldn't.
State: Ready