Release 4.0.0

• fix(gulp): clear modules cache to enable hot reloading (c1c8f80)
• fix(gulp): fix server hot reloading not restarting (57609bb)
• fix(gulp): fix hot reload (661639d)
• fix(loopback): fix lint errors (3086f12)
• doc(README): fix features (df428c7)
• doc(README): add features (ef7fe50)
• feat(async): add async module (7b17fc5)
• fix(loopback): change error to warning in console (3413b45)
• doc(README): fix usage docs (1063f8d)
• doc(README): fix typo (886c62a)
• doc(README): add vue-cli instructions (2ed4611)
• fix(auth): fix eslint errors (154897e)
• fix(loopback): add accessToken to logout method (4bac1b6)