Also refactored code a bit, removed printing functions from proctl
package and inlined them into command.

FDEs previously were loaded into a red/black tree and searched. This is
significantly more expensive than a binary search over a slice. Not sure
what I was thinking using a red/black tree - this binary search
implementation is significantly more efficient.

This commit fixes a race condition between Delve and the runtime of the traced process. When a new thread is created in the traced process, Delve takes note of it and then continue both the new thread, and the thread that called clone. If Delve attempts to use data in `runtime.allm` before the new `m->procid` is set, errors occur. The errors are due to Delve assuming any m with a procid of 0 is the main thread of the process (due to how theGo runtime allocates M's, only `clone`d threads have procid properly set. This causes certain events (like `next`) to happen twice to the main thread, because 2 m's in `runtime.allm` have a `procid` of 0, and also causes various other issues that prevent proper thread coordination from Delve.

Fixes #43

As of go version 1.4 the standard library syscall package is "locked
down" and code outside of the standard library is recommended to migrate
to the go.sys subrepository.

Reference: https://golang.org/s/go1.4-syscall