Pull request verification failed on CI

[sshuliar]

Hello,

CI server cannot build a pull requests:

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RubyGems installed the following executables:
	/home/travis/.rvm/rubies/ruby-2.4.1/bin/gem
	/home/travis/.rvm/rubies/ruby-2.4.1/bin/bundle
RubyGems system software updated
Creating alias 2.4 for ruby-2.4.1...
rvm
0.81s$ rvm use 2.4 --install --binary --fuzzy
Using /home/travis/.rvm/gems/ruby-2.4.1
$ export BUNDLE_GEMFILE=$PWD/Gemfile
cache.1
Setting up build cache
$ export CASHER_DIR=$HOME/.casher
0.03s$ Installing caching utilities
0.01s
7.62sattempting to download cache archive
fetching PR.5/cache-linux-trusty-3477f16fc8f58adeacd600592665e0f855c65695c6165c4cbdd8913a68ad2e2a--rvm-2.4--gemfile-Gemfile.tgz
fetching PR.5/cache--rvm-2.4--gemfile-Gemfile.tgz
fetching master/cache-linux-trusty-3477f16fc8f58adeacd600592665e0f855c65695c6165c4cbdd8913a68ad2e2a--rvm-2.4--gemfile-Gemfile.tgz
fetching master/cache--rvm-2.4--gemfile-Gemfile.tgz
could not download cache
cache.bundler
0.01s
1.45sadding /home/travis/build/hashicorp/nomad-ruby/vendor/bundle to cache
creating directory /home/travis/build/hashicorp/nomad-ruby/vendor/bundle
$ ruby --version
ruby 2.4.1p111 (2017-03-22 revision 58053) [x86_64-linux]
$ rvm --version
rvm 1.29.3 (latest) by Michal Papis, Piotr Kuczynski, Wayne E. Seguin [https://rvm.io]
$ bundle --version
Bundler version 1.16.1
$ gem --version
2.7.6
before_install.1
0.17s$ curl -sLo nomad.zip https://releases.hashicorp.com/nomad/${NOMAD_VERSION}/nomad_${NOMAD_VERSION}_linux_amd64.zip
before_install.2
0.29s$ unzip nomad.zip
Archive:  nomad.zip
  inflating: nomad                   
0.01s$ mkdir ~/bin
mkdir: cannot create directory ‘/home/travis/bin’: File exists
The command "mkdir ~/bin" failed and exited with 1 during .
Your build has been stopped.

[sshuliar]

#8 fix the issue
However there are failed test in master branch