v4.0.0

V4 validating the TRAVIS_TAG inside versiona (#3)

• Update Readme
• add tokens info
• update scripts to make them compliant with expected docs
• test mode should show what would happen, but not run
• TRAVIS_TAG should be analyzed internally to avoid copy-pasting the regexp
• remove complexity from travis yml

This version simplifies the versiona usage in .travis.yml
In V3:

script:
  - npm run check
  - |
    echo TRAVIS_BRANCH=$TRAVIS_BRANCH - TRAVIS_PULL_REQUEST=$TRAVIS_PULL_REQUEST - TRAVIS_TAG=$TRAVIS_TAG
    if [[ $TRAVIS_TAG =~ ^v[0-9]+\.[0-9]+\.[0-9]+(-beta\.[0-9]+)?$ ]]; then
      echo DEPLOY VERSION - TRAVIS_BRANCH=$TRAVIS_BRANCH, PR=$PR, BRANCH=$BRANCH
      TRAVIS_TAG=$TRAVIS_TAG GH_TOKEN=$GH_TOKEN npm run versiona
    fi

In V4:
The semver regexp will be analyzed internally and will do nothing if not matched:

script:
  - npm run check && TRAVIS_TAG=$TRAVIS_TAG GH_TOKEN=$GH_TOKEN npm run versiona