Icon wrapper around signing inputs

No issue

References https://github.com/TryGhost/Ghost-UI/commit/379a630e1bc1

- Adds `<span class="input-icon icon-mail">` around signing inputs to help match markup used elsewhere
Ignore tables with pg_ prefix in pg getTables.

Closes #3825
- Fixes an issue where a PostgreSQL extension may create
  a public table and it gets caught up in the migration process.
Merge pull request #3837 from jaswilli/issue-3825

Ignore tables with pg_ prefix in pg getTables.
Merge pull request #3820 from PaulAdamDavis/input-icons

Icon wrapper around signing inputs
testing
only run pg
debug
debug
debug
debug
debug
debug
debug