version 1.5.0.rc3.snapshot1 bump

fix the version naming in order to use the sem_ver convention for tha package name and the rubygems one for the gem

make the logstash.gemspec look alike the logstash-core

Fixes elastic#2958

New lines for rc2

Fixes elastic#2788

bump s3

Fixes elastic#2773

expand attributes in ListingBlocks, sync to logstash-docs version

Fixes elastic#2216

refactor to use single gem dir vendor/bundle, use Bundler::CLI, .lock…

… files naming

Fix typo

Merge pull request elastic#1336 from colinsurprenant/export_cypher

exlude export_cypher tag in specs

Update changelog

actually build rpm/debs

Merge branch 'master' into 1.4.x

* master:
  correct email config hash options
  minor updates, submitting two PRs as one
  put the pencil to graphite
  touch up email doc