[FEATURE] Attribute "maxItems" on Form / MultiUpload

Added due to a need arisen in a legacy site but is useful enough that it should be made public even if FED is obsolete. If and when the Multiupload ViewHelper gets ported, this will then be included.
Merge pull request #24 from NamelessCoder/maxitemsonmultiupload

[FEATURE] Attribute "maxItems" on Form / MultiUpload
[BUGFIX] Incorrect reading of preset value in MultiUpload ViewHelper
[BUGFIX] Incorrect check for "storedValue" set in MultiUpload ViewHelper
[BUGFIX] Incorrect return value in MultiUpload ViewHelper
[BUGFIX] Proper boolean comparison in MultiUpload ViewHelper
[BUGFIX] Incorrect default return value in MultiUpload ViewHelper
[TASK] Rebasing to use latest Flux changes
Merge pull request #26 from NamelessCoder/rebase

[TASK] Rebasing to use latest Flux changes
Merge pull request #25 from NamelessCoder/multiupload

[BUGFIX] Corrections for retrieving stored value in MultiUpload ViewHelper
[BUGFIX] Remove remaining reference to removed class
Merge pull request #28 from NamelessCoder/rebase

[BUGFIX] Remove remaining reference to removed class
[TASK] Proper check for empty value in MultiUpload ViewHelper
Merge pull request #27 from NamelessCoder/multiupload

[TASK] Proper check for empty value in MultiUpload ViewHelper
[TER] 5.0.4