better buildpack format error

[finishes #42502469]
simplify 'vmc map'

* now focuses solely on apps
* host and domain are separate args, with host optional (default "")
* app argument is the first one, like other app-centric commands

[finishes #40325679]
don't save auth token if it becomes nil

[#43577727]
Update README.md
fix vmc push with url

takes separate --host and --domain arguments (accepts "none" for both)
console app rspec matchers (wip)
initial test framework

* use a better ruby expect equivalent that tracks full output
* have travis run integration specs against 1.8.7 and 1.9.3
* disable integration specs on ruby 1.8.x