Remove irrelevant boost.simd.memory related includes from unit tests.
Restructured documentation so Boost modules are properly setup

Boost.SIMD was made of libraries which cant be inserted inside
another libraries. Boost modules went up a level in the doc
hierarchy to allow this to work properly.
Move memory related function from simd/sdk to simd/memory
Added low level system wrapper for aligned (de/re)allocation handling
Optionnal global new/delete overloads using aligned allocation functions.
Added aligned_object class to imbue a given type with aligned new/delete overloads
Added aligned stack buffer creation macro
Homogeneize extract and insert return types and semantic

Tests have been changed accordingly and complex case have
been added in proper module.
Remove deprecated components:

* memory::byte is now deprecated
   This typedef where serving little to no purpose. It has been
   removed and all code using it now sue void* instead.

* boost::simd::memory namespace is deprecated
  Most element of Boost.SIMD.Memory lived in boost::simd. Remaining parts
  of boost::simd::memory:: have been moved and dependent code have been
  modified.
Added contents to memory documentation
Move some component to new simd/preprocessor location

This include :

* alignment macro
* stack_buffer macro
* new/delete overload macro
* memory/parameters.hpp
* config.hpp
Remove warning C4290 spam

MSVC outputs warning C4290 whenever boost/simd/memory/new.hpp
is used. Turns out its exception support is poor and its <new>
header is not conformant woth respect to exception specifications.
Further research shows that Android has a similar issue (as per
Mozilla bug #578546). This commit add a local macro that turns
off the throw(std::bad_alloc) on those compilers.
More documentation fixed and refurbished
Add tests for reallocate/reuse
Memory functions use dispatch_call directly
Move core memory to core.memory and fix dependencies along
Move bitwise_cast to be a proper function of sdk.
Refurbished prefetch

Split read and write prefetch and renamed/fixed value of strategies hints
load/store Renaming

boost::simd::load is now boost::simd::aligned_load
boost::simd::store is now boost::simd::aligned_store
boost::simd::unaligned_load is now load
boost::simd::unaligned_store is now store

Impacted files have been modified accordingly
Added a @usage{} doxygen alias for example insertion