[ticket/12559] Add forum setting to limit subforum legend

Squashed all commits, they were basically just typos and errors

PHPBB3-12559
[ticket/12559] Applied DeMorgan and removed unnecessary true:false

PHPBB3-12559
[ticket/12334] Add PROFILE_FIELD_VALUEID template var

PHPBB3-12334
[ticket/12334] Added field_novalue fall-back as requested

PHPBB3-12334
[ticket/12334] Implemented get_profile_valueid method

PHPBB3-12334
[ticket/12334] Changed from valueid to value_raw

PHPBB3-12334
[ticket/12334] Added test get_profile_value_raw

PHPBB3-12334
[ticket/12334] Dropdowns cannot be tested this way

PHPBB3-12334
[ticket/12334] Removed tests

Will be implemented in #2459

PHPBB3-12334
[ticket/12408] Add quick setting for "default guest style" to ACP

PHPBB3-12408
[ticket/12408] Simplified queries

PHPBB3-12408
[ticket/12408] Code cleanup

Rebased to see if travis will finally play along

PHPBB3-12408
[ticket/12408] Public functions and updated doc block

PHPBB3-12408
[ticket/12408] Changed lang vars, added fieldset and removed "default"

PHPBB3-12408
[ticket/12559] Updated copyright information

PHPBB3-12559
[ticket/12646] Add data-f attribute to breadcrumb links

PHPBB3-12646
[ticket/12646] Changed index/home data attr & updated subsilver

PHPBB3-12646
[ticket/12562] Add max-width to proSilver

PHPBB3-12562
[ticket/12562] Updated to 1140px

As per suggestions

PHPBB3-12562
[ticket/12562] 8 * 12 * 12 = 1152px ( + 12px bleed)

PHPBB3-12562