Use if COMMAND to detect if a function is defined

The SimpleITKData target was not being created because the incorrect
conditional was used to detect a defined function or macro.

Change-Id: Iaf64ee05dd1fb91fd8a00bd7b38f6bd9435ecfc8
Move Java test examples to example directory

The add_test wrapper for java has been moved to the common cmake
file.

The java compilation of each example is now a separate target.

Change-Id: I6fd267f4109b09c09ad70a562bc80488ac2fcc5f
Moving R add test wrapper to common cmake file

Change-Id: I573862b32d5750ce9d7dd07a1e81af0a700bb011
Adding missing R SimpleGaussian example

A couple of bugs and typeos were corrected in the example.

Change-Id: Ie904cdf13c24ca7291046f3459c3b3b76449b6d0
Moving CSharp examples test to example directory

Move add_test for CSharp wrapper to common cmake file.

Change-Id: Ib624bcd3af678cbbc66231a95e82fd978c41d235
Always allow sitk_add_?_test

The languages specific version of sitk_add_test where conditionally
defined dependent on the language being enabled. This caused all usage
of these function to be surrounded in the conditional. By moving the
conditional inside the function and turning it into a noop, the
numerous conditional could be removed.

Change-Id: Id394b362bba1c66df2578d75ce02b5e2c2a3a534
In test assert array is not empty

This prevent a segfault of the test when there is no data.

Change-Id: I96fe5d36b4ad46788592ff962c10837cbd13d1f7
Merge topic 'SIMPLEITK-536_CreateTransformTestingInfrastructure' into next

925ce8fe In test assert array is not empty
335e674b Always allow sitk_add_?_test
f1273573 Moving CSharp examples test to example directory
bf78057b Adding missing R SimpleGaussian example
213f7bc8 Moving R add test wrapper to common cmake file
1ac9bfbe Move Java test examples to example directory
b91ed2a0 Use if COMMAND to detect if a function is defined