Improve test coverage and quality

[Eggbertx]

Packages

• cmd/gochan
• cmd/gochan/migration/internal/common
• cmd/gochan/migration/internal/gcupdate
• cmd/gochan/migration/internal/kusabax
• cmd/gochan/migration/internal/pre2021
• cmd/gochan/migration/internal/tinyboard
• building
• config
• events
• gcplugin
• gcsql
• gcsql/initsql
• gctemplates
• gcutil
• manage
• posting
• posting/geoip
• posting/uploads
• posting/uploads/inituploads
• server
• server/serverutil

Templates

Template tests should be stored in the pkg/gctemplates/templatetests directory, with the package set to templatetests_test. Because they would be calling functions from other packages, they might not affect code coverage as reported by go test -cover, so they can be seen as integration tests.

• banpage.html
• boardpage.html
• captcha.html
• catalog.html
• consts.js
• error.html
• front.html
• front_intro.html
• manage_announcements.html
• manage_appeals.html
• manage_bans.html
• manage_boards.html
• manage_dashboard.html
• manage_filebans.html
• manage_fixthumbnails.html
• manage_ipsearch.html
• manage_login.html
• manage_namebans.html
• manage_recentposts.html
• manage_reports.html
• manage_sections.html
• manage_staff.html
• manage_templateoverride.html
• manage_threadattrs.html
• manage_viewlog.html
• manage_wordfilters.html
• movethreadpage.html
• page_footer.html
• page_header.html
• postbox.html
• post_edit.html
• post_flag.html
• post.html
• threadpage.html
• topbar.html