Main Tasks around Google Places API

[x] limit the user input, especially the upper limit of "quantity"
[x] for categories, combine multiple types since google places API don't support searching for multiple types at the same time
[x] further change the types, enlarging the search range (especially sports...), self-defined keyword, add some explanations to users
[x] get user transportation method -> use corresponding radius & prepare for usage in route API (Q: Do i only use it as a calculation for routes, or use it to decide the nearby search radius? A: Only use for routes, since search radius cannot be adjusted in most scenarios!)

Add-on Tasks/Issues:

[x] waiting time for output is too long (solution: website UI "please wait a moment" prompt)
[x] add limits for ratings & radius (currently too big)
[ ] change the type/keyword-led nearbysearch URL to maximize length of attractionArr
[ ] change place input box into google-based (directly inputting valid address/city name), e.g. "USC" cannot be processed, this box is necessary (QUESTION: must use google api key in html script. Is there a way to avoid such exposure?)

BigFace1V10 / trip-generator