BUG: Fix linking of factory register method on static windows

This patch fixes link errors such as the following:
error LNK2019: unresolved external symbol "__declspec(dllimport) void
__cdecl itk::BioRadImageIOFactoryRegister__Private(void)"

Remove ITK_ABI_IMPORT declaration attribute from private factory
registration methods declared in the automatic registration from
UseITK. ITK_ABI_IMPORT is always defined to import, independently of
static or shared itk libraries. The private factory registration
method must not be defined as imported from static libraries on windows.

Change-Id: I7066828602f00b59403726e1acc12785f9da49f7
STYLE: Fix some style errors reported in continuous test

Change-Id: I4775f731ae2c29efaf44bf87bf012322aed8021f
Merge topic 'FixSomeStyleInVectorTests'

4c6d5a1 STYLE: Fix some style errors reported in continuous test
Merge topic 'FixStaticWindowsLinking'

bbda0b4 BUG: Fix linking of factory register method on static windows