Continious Deploy to NPM with @next tag when the MINOR version number is odd(in developing branch)

[huan]

According to #905, when the minor version number in semvar is odd, it means it comes from a developing branch, and it's very like UNSTABLE.

odd Examples: (UNSTABLE, in developing)

• 0.15.1
• 0.15.2
• 1.1.1
• 1.1.2

even Examples: (STABLE, production)

• 0.16.1
• 0.16.2
• 1.0.1
• 1.0.2

At the same time, we publish all the version to NPM when the code base passed the Automatic Testing by Travis CI.

We should only publish to NPM via CI/CD for the STABLE/PROD version for master branch, which means we should limit it to the version number is even.

See Also

• https://stackoverflow.com/q/43210945/1123955
• https://docs.npmjs.com/misc/config#environment-variables

[huan]

Done.

https://github.com/Chatie/wechaty/blob/5fcaa398a049b4090ecd4693edaeffdae80bc90e/.travis.yml#L48-L53