fix(deps): missing deps

fix(require): Fix wrong require

fix(gl-react-image): broken -> downgrade to for gl-react-v2

re #50

fix(Travis): fix travis yaml file

feat(filePath): Support filePath prop to save to file

Closes #39

fix(background): Use transparent background on Android

feat(PixelRatio): Added PixelRatio to set pixel density

refactor(TravisCI): fix broken build

fix(Declaration): declaration fix

Merge pull request #13 from stoffern/travis

Travis