Currently Travis supports only Ubuntu 12.04 linux 2.6 VMs which are
terribly outdated, and trying to track down why it's hanging on Travis
but not on other similar VMs is more trouble than it's worth at the
moment.

Certainly another more appropriate and up to date CI solution should be
explored.

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

Enable usage of dr1-dr3.  Clear control bits when a breakpoint
is disabled. Use DR_LEN_1 instead of DR_LEN_8 so breakpoint work on
unaligned adresses.

Fixes #51.

Improves error message on systems that delve is failing on.

There were certain instances where the calculation of the stack frame
was incorrect, causing for garbage to be returned by a print command.