Enhance search engine UI

[john-hu]

To support enhanced search options:

• [x] diet search
• [x] easy cook (cook time less than x mins)
• [x] easy prepare (ingredient count less than x)

To support better UI:

• [ ] diet labels
• [x] cook time info
• [ ] source site

[AngusHsu]

Easy prepare => ingredient count less than 5

[AngusHsu]

Do a conditional search for vegetarian

[AngusHsu]

Close it and continue on #80