Revert "Issue #1331486 by katbailey, chx, sun, beejeebus, amateescu: Move module_invoke_*() and friends to an Extensions class. Broke core tests after commit."

This reverts commit c80c3e18.

Issue #1331486 by katbailey, chx, sun, beejeebus, amateescu: Move module_invoke_*() and friends to an Extensions class.

Issue #184010 by webchick, catch, bdone, Pasqualle, lilou, cafuego, Elvar: Add #anchors to modules administration page.

Issue #1824778 by vijaycs85, ACF, pcambra, cam8001: Covert css_gzip_compression() and js_gzip_compression() variables to CMI system.

Issue #1571632 by cosmicdreams, marcingy, justafish, chx, KarenS, aspilicious, disasm, swentel, dawehner, rvilar: Convert regional settings to configuration system.

Issue #1168246 by sun, mgifford, Manuel Garcia, mbrett5062, ry5n, Everett Zufelt, nod_, aspilicious, deviantintegral, tim.plunkett: Freedom For Fieldsets! Long Live The DETAILS.

Issue #1292470 by sun, tim.plunkett, Berdir, moshe weitzman, pcambra, Niklas Fiekas, andypost et al: Convert user pictures to Image Field.

Issue #1790280 by nod_, Bojhan, Wim Leers, danillonunes, deviantintegral, Kiphaas7, benjifisher, sun, yoroy, Everett Zufelt, jenlampton, aspilicious: Module page redesign 2.0.

Issue #1269742 by katbailey, beejeebus, pwolanin, g.oechsler, ksenzee: Make path lookup code into an pluggable class.

Issue #492720 by pivica, seutje, nod_, JamesAn, sun: Refactor system.js file and use Drupal form states and form ajax.

Issue #1810652 by xjm: Fixed admin/config/system/site-information still references the default content feed when node.module is disabled.

Issue #1608842 by chx, alexpott, sun, effulgentsia, beejeebus, tim.plunkett et al: Replace list of bootstrap modules, enabled modules, enabled themes, and default theme with config.

Issue #1480854 by tim.plunkett, Noyz, Bojhan, yoroy, kika: Convert operation links to '#type' => 'operations'.

Issue #1326618 by Albert Volkman, ykhadilkar, oriol_e9g, daniel_j, xenophyle: API docs cleanup for locale module

Issue #1276908 by jessebeach, nod_, moshe weitzman, lewisnyman, webchick: Fixed Administrative tables are too wide for smaller screens.

Patch #1161486 by rootatwc, sun, andypost, catch, marcingy, aspilicious, cam8001: Move IP blocking into its own module.

Issue #1468328 by Berdir: Move file entity info, managed file, and file usage functionality into File module.

Issue #1737148 by nod_, SebCorbin, larowlan, tim.plunkett, Albert Volkman, nick_schuch, sun: Explicitly declare all JS dependencies, don't use drupal_add_js().

Issue #1669902 by alexpott, aspilicious, sun: Adjust system.performance configuration for new guidelines.

- Patch #1397882 by sun, catch: system_theme_settings_submit() does not properly clean up submitted form values.

- Patch #542828 by sun, Pasqualle, marcingy, Gábor Hojtsy: do not special case disabled admin theme.

Issue #304540 by Rob Loach, marcingy, typhonius, BrockBoland, jaredsmith: Fixed Disable themes when theme engine or base theme arn't available.

Issue #1493108 by marcingy, Mike Wacker, sun, kbasarab, Berdir, Rok Žlender, cosmicdreams, alexpott: Convert logging and error settings to configuration system.

Issue #1496458 by swentel, pcambra, n3or, kbasarab, sun, marcingy: Convert maintenance mode settings to configuration system.

- Patch #1496462 by acrollet, sun, cosmicdreams, Niklas Fiekas, aspilicious: convert RSS publishing settings to configuration system.

Issue #950956 by tim.plunkett, aspilicious, jenlampton, chx, Rob Loach: Remove Dashboard module until/unless such time as it's more useful.

- Patch #1493098 by sun, jcisio, pcambra, Pol, wamilton, Rok Žlender, beejeebus: convert cron settings to configuration system.

Issue #1496542 by cosmicdreams, sun, chx, vasi1186, aspilicious, alexpott, nadavoid, Pedro Lozano, disasm, andypost | heyrocker: Convert site information to config system.