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[MartijnCuppens]

Prevent files .travis.yml, .jshintrc and LICENSE-MIT (licence is included in package.json) files from being published to npm

Difference:

npm notice 📦  array-initial@1.1.0
npm notice === Tarball Contents === 
npm notice 259B  .jshintrc   
npm notice 1.1kB LICENSE-MIT 
npm notice 517B  index.js    
npm notice 933B  package.json
npm notice 905B  README.md   
npm notice 132B  .travis.yml 
npm notice === Tarball Details === 
npm notice name:          array-initial                           
npm notice version:       1.1.0                                   
npm notice package size:  2.0 kB                                  
npm notice unpacked size: 3.8 kB                                  
npm notice shasum:        ae472e519e86046fbbcaac9117ee501d6a60af22
npm notice integrity:     sha512-h1zP1qnXmTi2k[...]bZgRnTqZnZXRA==
npm notice total files:   6

npm notice 📦  array-initial@1.1.0
npm notice === Tarball Contents === 
npm notice 517B index.js    
npm notice 958B package.json
npm notice 905B README.md   
npm notice === Tarball Details === 
npm notice name:          array-initial                           
npm notice version:       1.1.0                                   
npm notice package size:  1.1 kB                                  
npm notice unpacked size: 2.4 kB                                  
npm notice shasum:        4d0a4be87f21fa1eb84e79dccbd081228ec52551
npm notice integrity:     sha512-kYZ/BGMU0You6[...]8H2h3m442bi3A==
npm notice total files:   3