Add lintcode support

[Sam-Si]

Please review previous closed issues before filling out a new one! Duplicate issues will be closed without comment.

Is your feature request related to a problem? Please describe. No. The feature request isn't related to a problem.

Describe the solution you'd like Like my leetcode solution is being synced. It would be great if lintcode solutions can be synced as well.

Describe alternatives you've considered The alternative to this is manually uploading your solutions which is boring.

Additional context Since leetcode and lintcode are very similar. This might not be very big of a change. Lintcode contains a few of the premium questions for leetcode so that's great.

Link: https://www.lintcode.com/