[BUGFIX] Clone response and re-process in Flux sub-Controller class

This bug fix addresses a problem with using the $this keyword from within FluxControllers; methods would be called statically and would be missing a class context. Fixed by cloning the response and using processRequest to execute the desired controller if the extension name is different from the host extension.
[TASK] Simplify field structure compilation process

This change applies a huge cleanup in field structure (TCEforms) compilation when using Flux field ViewHelpers. Before, a collection of special StructureProviders were used - now, this all happens inside the ViewHelper.

There is still a lot which can be cleaned and simplified even further - for example, the configurations being built definitely contain redundant variables. But this initial simplification cuts away a lot of redundant source code and makes the logic easier to read.
[TASK] Various cleaning in FluxService

It's cleaning time - fixing a few boolean/null comparison orders and implements a previously unified API method, having the side benefit of also respecting the cache in one additional case: when reading a list of available content areas from a content element by UID (which happens when pasting content elements).
[TASK] Remove a superfluous internal cache use
[TASK] Save a few µs by returning an array original instead of copy
[BUGFIX] Consider recursive array of values in cache key
[BUGFIX] Missing alt. CTypes in nested child content

Fixes: FluidTYPO3/fluidcontent/issues/40
Merge pull request #97 from NamelessCoder/servicecleanup

[TASK] Service cleanup: CGL, shifts to API, mini performance boosts
Merge pull request #95 from NamelessCoder/subrequests

[BUGFIX] Clone response and re-process in Flux sub-Controller class
[BUGFIX] Prevent possible E_NOTICE by using isset() vs is_array()
Merge pull request #98 from NamelessCoder/issue/40

[BUGFIX] Missing alt. CTypes in nested child content
Merge pull request #99 from NamelessCoder/issetarray

[BUGFIX] Prevent possible E_NOTICE by using isset() vs is_array()
[BUGFIX] Attempt to create Singleton with ObjectManager->create()
Merge pull request #96 from NamelessCoder/fieldstructureproviderpurge

[TASK] Simplify field structure compilation process