BUG: Using static const variable causes ld error when using dynamic libraries

Static const variables yeld STB_GNU_UNIQUE symbols in shared libraries, and prevent these libraries to be properly unloaded. As a result, a program using dynamic libraries loading including calls to itk::MattesMutualInformationImageToImageMetric will return the following error whenever it ends :

Inconsistency detected by ld.so: dl-close.c: 731: _dl_close: Assertion `map->l_init_called' failed!

This patch only replaces the static const variables by const variables.

The pre-commit hook made me do the style changes. I applied the requested changes in this new version.

Change-Id: I5862ff5a965599dbf2a4cc1b48b5a4931588653b
BUG: Remove initially available ITK_WRAP_JAVA cmake option

Currently Java WrapITK needs work, an does not build correctly. This
patch removes the option initially available. The option will still
become available after ITK_WRAPPING is enabled.

Change-Id: I8d552555d72d95b5fbf05b87b94527aac1025960
Merge topic 'WrapITKNoEasyJavaOption'

04c9485 BUG: Remove initially available ITK_WRAP_JAVA cmake option
Merge topic 'static_const_removal'

d74f4d8 BUG: Using static const variable causes ld error when using dynamic libraries