[ticket/11314] Cleanup core.js coding

function errorHandler() was used in returnHandler() before it was defined.
The unused variable alert has been removed from errorHandler(). Overuse of
the var keyword for the variable sign has been removed and the if
statement has been simplified. The definition of the variable i has been
moved outside of the for loop definition. The var keyword shouldn't be
used inside the definition of the for loop.

PHPBB3-11314
[ticket/11314] Add missing semi-colons

Omitting the semi-colon is not legal behavior for JavaScript.

PHPBB3-11314
[ticket/11314] Use return variable instead of overusing the return keyword

Use a return variable and modify it to our needs.

PHPBB3-11314
[ticket/11314] Add missing "use strict" to timezone.js files

PHPBB3-11314
[ticket/11314] Fix whitespace issues

PHPBB3-11314
[ticket/11314] Add missing radix parameters

PHPBB3-11314
Merge branch 'develop' of https://github.com/phpbb/phpbb3 into ticket/11314
[ticket/11314] Fix issues mentioned in jshint report

Additionally, the editor.js files are now the same file in both
subsilver2, prosilver, and the acp.

PHPBB3-11314
[ticket/11314] Fix JSHint issues in adm editor.js

This time without changing the behavior.

PHPBB3-11314
[ticket/11314] Modify files to comply with coding standards

PHPBB3-11314
Merge branch 'develop' of https://github.com/phpbb/phpbb3 into ticket/11314

Conflicts:
	phpBB/styles/prosilver/template/timezone.js
[ticket/11225] Deletion of unused mcp_jumpbox.html file

The file/template is no longer used(as mentioned in it).

PHPBB3-11225
[ticket/11494] Fix memberlist leaders functional tests

The scope of the crawler should be reduced to the specific table

PHPBB3-11494
[ticket/11491] Move file to correct directory

PHPBB3-11491
[ticket/11491] Fix class name of functional test

PHPBB3-11491
[ticket/11491] Add extension_acp_test.php to functional group

PHPBB3-11491
[ticket/11491] Fix path to the ext/ folder

PHPBB3-11491
[ticket/11491] Correctly remove the store/temp_ext/ directory after use

PHPBB3-11491
[ticket/11491] Only copy files from phpBB/ext/ the directory exists

PHPBB3-11491
[ticket/11491] Copy files back only if we saved them previously

PHPBB3-11491