Merge branch 'hotfix/3247' into develop

Close #3247
Fix (un)subscribe operation. The http (un)subscription request was never sent to the hub
FileInputTest mock fix; File PRG fix
File Filter unit test coverage for FILES array
fixed license tag generation
Merge branch 'hotfix/zend-form-allow-input-filter-preference' of git://github.com/mwillbanks/zf2 into feature/form-merge-specs
Merge branch 'feature/form-merge-specs' into develop

Close #3218
Merge branch 'fix/file-upload-filtering' of git://github.com/cgmartin/zf2 into hotfix/3246
Merge branch 'hotfix/3246' into develop

Close #3246
Merge branch 'hotfix/3248'

Close #3248
Merge branch 'hotfix/3248' into develop

Forward port #3248
Merge branch '#2912' of git://github.com/robertboloc/zf2 into hotfix/3250
[#3218] CS fixes

- whitespace after operators
- use identity operator when testing against null
- array/argument indentation
Merge branch 'hotfix/3250'

Close #3250
Fix #2912
Merge branch 'hotfix/3250' into develop

Forward port #3250
subject prepend text in options for Log\Writer\Mail

Cherry-picked from https://github.com/tolean/zf2 addb497

Conflicts:
	library/Zend/Log/Writer/Mail.php
	tests/ZendTest/Log/Writer/MailTest.php
Merge branch 'hotfix/3252'

Close #3252
Merge branch 'hotfix/3252' into develop

Forward port #3252

Conflicts:
	library/Zend/Log/Writer/Mail.php
	tests/ZendTest/Log/Writer/MailTest.php
Merge branch 'hotfix/2678-sqlsrv-createStatement-bug' of git://github.com/syniq/zf2 into syniq-hotfix/2678-sqlsrv-createStatement-bug
Allow Forms to have an InputFilterSpecification