Gig application error page fixes

[kkartunov]

Update the page:

• add the error message as returned from API to that “oops” page
• add the text: “Please send us an email at gigwork@topcoder.com with the subject ‘Gig Error’ and paste the URL for the gig you are attempting to apply for so that we know of your interest”
• add a white button - "VIEW OTHER GIGS" linked to the gig listings page

[kkartunov]

For QA: an easy way to test this is by mocking the offline state in the network tab.

[SathyaJayabal]

@kkartunov , I dont find this deployed yet.

[SathyaJayabal]

verified on qa env

[SathyaJayabal]

verified on staging - develop branch