[2011] Improve SysML validation to be more modular

[flatombe]

Notes:

• Had to tweak JDT formatter setting "org.eclipse.jdt.core.formatter.alignment_for_enum_constants" so we get a newline for each enum literal even if it does not have Javadoc.
• Had to tweak JDT formatter setting "org.eclipse.jdt.core.formatter.continuation_indentation_for_array_initializer" to be in-line with the formatting expected by Checkstyle.

Bug: #2011

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