Fixes #106

Splits out type parsing and go-specific Type hierarchy from
x/debug/dwarf, replace x/debug/dwarf with debug/dwarf everywhere,
remove x/debug/dwarf from vendoring.

* Fix various issues detected by megacheck

I've ran honnef.co/go/tools/cmd/megacheck and fixed a few of the
things that came up there.

* Cleanup using Gogland

Fixes #885

* pkg/proc: use golang.org/x/arch/x86/x86asm

instead of rsc.io/x86/x86asm

* pkg/dwarf: migrate to github.com/pkg/profile

from github.com/davecheney/profile

* scripts: keep script go files from being considered for the build

scripts/gen-*.go files are scripts for generating documentation
files and don't follow the typical Go package layout. Expected
usage is like

   go run scripts/gen-cli-docs.go

* vendor: update vendored packages

There were many changes in delve, and go tool chains since last
vendored package update. I just rerun godpes from scratch.

$ rm vendor/*
$ rm Godeps/Godeps.json
$ go list ./... | grep -v /vendor/ | grep -v /scripts/ | go get -u -t
$ go get -u github.com/mattn/go-colorable
$ go get -u github.com/mattn/go-isatty
$ go list ./... | grep -v /vendor/ | grep -v /scripts/ | godeps save