Bump minimum eslint version to 3.19.0
Bump minimum eslint version to 3.19.0

The previously referenced eslint version is not compatible with our code base.
For example, rule "prefer-promise-reject-errors" requires 3.14.0.

macroplant/pdf.js,showpad/mozilla-pdf.js,Snuffleupagus/pdf.js,timvandermeij/pdf.js,nawawi/pdf.js,macroplant/pdf.js,nawawi/pdf.js,mozilla/pdf.js,skalnik/pdf.js,Shoobx/pdf.js,adlerweb/pdf.js-Touch,mainegreen/pdf.js,mozilla/pdf.js,timvandermeij/pdf.js,Snuffleupagus/pdf.js,mainegreen/pdf.js,nawawi/pdf.js,showpad/mozilla-pdf.js,xavier114fch/pdf.js,Rob--W/pdf.js,websirnik/pdf.js,Rob--W/pdf.js,websirnik/pdf.js,caremerge/pdf.js,Snuffleupagus/pdf.js,Shoobx/pdf.js,macroplant/pdf.js,xavier114fch/pdf.js,mukulmishra18/pdf.js,showpad/mozilla-pdf.js,Shoobx/pdf.js,adlerweb/pdf.js-Touch,mukulmishra18/pdf.js,caremerge/pdf.js,skalnik/pdf.js,mozilla/pdf.js,timvandermeij/pdf.js