Merge pull request #10426 from tkrajcar/rescue-h1-fix

Add styling to h1 for default rescue layout
Add note about libpq connection params in CHANGELOG
Merge pull request #10431 from larskanis/add_note_about_libpq_params_in_changelog

Add note about new database parameters for PostgreSQL adapter in CHANGELOG
Merge pull request #10424 from markevich/fix_test_prepare

Restore ActiveRecord connection to original environment after rake:db:test:prepare task.