v0.2.5

Update notes: None

Changes:

• [FEATURE] #880 Add association helper @Azdaroth
• [FEATURE] #948 Add length to collections @mfazekas
• [FEATURE] #957 Add slice method to collections @alexparker
• [ENHANCEMENT] #796 improve normalizedRequestAttrs helper @jbailey4
• [ENHANCEMENT] #928 add a default passthrough @anulman
• [ENHANCEMENT] #987 Added falsy condition to exclude faker.js & pretender.js in production build @renpinto
• [BUGFIX] #984 Blueprint.prototype.insertIntoFile is async @stefanpennar
• [BUGFIX] #905 Serialize on key instead of modelName @jessedijkstra
• [BUGFIX] #950 fix JSON:API includes @deepflame
• General improvements @jessedijkstra @bantic @alecho @alexparker @mfazekas @Azdaroth