Merge branch 'version/bump'

Bump to 2.3.4dev
change is_null to $value compare to null
for consistency with #3520
Merge branch 'hotfix/#6643-is-null-removal'

Close #6643
Fixes cs : space after if and elseif in deep conditional
iirc, I already sent a request to php-cs-fixer repository for its feature but it won't be implemented because it require to much logic
space after close parenthesis
Merge branch 'hotfix/#6743-if-spacing-psr2-compliance'

Close #6743
PHPCS fixes for Zend\Dom
Merge branch 'cs/#6699-zend-dom-psr-2-compat'

Close #6699
added zendframework/zendxml into require at Zend\Json's composer.json
move zendxml to suggest and mark to Json::fromXml() as @deprecated
update comment on suggest
Bug fix: Removes length limit (of TLD) when validating a hostname

The regular expression matching a tld in a hostname was limited to 2 to 10 chars.
This limit was reached with new gTLDs like .photography. Added this use case to
tests and removed length limit of 10 chars to allow new TLDs like .photography.
Set fixed length limit for validating TLDs in hostname validator.
Merge branch 'hotfix/#5992-remove-tld-length-limitations'

Close #5992
Update EventManagerInterface.php

Fixing the documentation, the callback is stopping propagation when returning true, not false as documented in this interface.
Merge branch 'hotfix/#6867-fix-eventmanagerinterface-short-circuiting-response-reaction-value'

Close #6867
See facebook/hhvm#1221
See facebook/hhvm#2018
See https://github.com/facebook/hhvm/blob/HHVM-3.3.1/hphp/doc/inconsistencies

Conflicts:
	tests/ZendTest/Http/ClientTest.php
fixing http query parameters

Zend\Stdlib\Parameters is not converted to PHP array in HHVM
Merge branch 'hotfix/#6231-fix-http-query-parameters-to-array-cast-on-hhvm'

Close #6231
Memcached returns FALSE on failure
... so it's not required to check for NULL, too.
The note Memcached returns NULL was a miss information in changelog of memcached-2.0