Fix linter errors

# Conflicts:
#	lib/contracts/contribution.js
#	lib/contracts/contributor.js
#	lib/contracts/proposal.js
#	lib/kredits.js
#	lib/utils/pagination.js

lib/utils/preflight.js

@@ -1,9 +1,9 @@
 class Preflight {
-  constructor(kredits) {
+  constructor (kredits) {
     this.kredits = kredits;
   }
 
-  check() {
+  check () {
     return this.kredits.ipfs._ipfsAPI.id()
       .catch((error) => {
         throw new Error(`IPFS node not available; config: ${JSON.stringify(this.kredits.ipfs.config)} - ${error.message}`);