releases/2014-01-11

    Fixing def of hem.poi system. Adding provenance notes on relationships. Starting to address issue #388
    Definition improvements. Endochondral element refactoring continued
     * neuropore fixes
      * fixed defs
      * split lamina terminalis into embryonic and mature
    fixed unsatisfiable class, equivalence axioms and naming conventions. Issue #382
    new terms:
     UBERON:0015117	lamina terminalis of cerebral hemisphere
     UBERON:4300081	mesopterygium element
     UBERON:4300082	metapterygium element
     UBERON:4300083	propterygium element