isNode check causes unsafe-eval error when using strict CSP policies

[lfittl]

Ever since c14972e the following will happen in the browser (e.g. Chrome 55) when one has a content security policy that forbids eval:

Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an
allowed source of script in the following Content Security Policy directive

This is caused by the following line in https://github.com/kadirahq/lokka-transport-http/blob/master/lib/index.js#L7:

const isNode = new Function('try {return this===global;}catch(e){return false;}');

Unfortunately I'm not able to enable eval just for lokka, and this currently forces me to remain at 1.4.0, the last version that didn't have this check.

Any chance this check could be replaced with something else?