Display error messages in modal
Add test, style fixes, and other minor error fixes
Add unit test
Add unit test and merge
Add unit test
Minor change
Revert "Merge pull request #1 from kyungmin/validation-error"

This reverts commit b46d4fd1e5a5a16b1dc8e89335ad21a093fdf17b, reversing
changes made to c20af80dc8cc3ad5083ffc75d4fcffbfc1854bf2.
Add unit/integration test
format