Fix perf regression in `getPartials()`
Fix perf regression in `getPartials()`

This _drastically_ improves the perf of `getPartials()` by being sure to pass `options` along to `getTemplates()`, by not passing these options, `getTemplates()` was never signaled to use the cache.

camabeh/express-handlebars,rstr74/express-handlebars,jeanpan/express-handlebars,lijanele/express-handlebars,confuser/express-handlebars,molant/express-handlebars,ericf/express-handlebars,blendlabs/express-handlebars,edorsey/express-handlebars,michaeljunlove/express-handlebars,iscarecrow/express-handlebars,mello151/express-handlebars