Get rid of deprecate warnings

[ryuukk]

They should be fixed before they become errors

dsymbol\src\dsymbol\conversion\first.d(958,7): Deprecation: function `dparse.ast.IfStatement.identifier` is deprecated - use condition.identifier
dsymbol\src\dsymbol\conversion\first.d(963,52): Deprecation: function `dparse.ast.IfStatement.identifier` is deprecated - use condition.identifier
dsymbol\src\dsymbol\conversion\first.d(964,46): Deprecation: function `dparse.ast.IfStatement.identifier` is deprecated - use condition.identifier
dsymbol\src\dsymbol\conversion\first.d(965,8): Deprecation: function `dparse.ast.IfStatement.type` is deprecated - use condition.type
dsymbol\src\dsymbol\conversion\first.d(966,42): Deprecation: function `dparse.ast.IfStatement.type` is deprecated - use condition.type
dsymbol\src\dsymbol\conversion\first.d(970,36): Deprecation: function `dparse.ast.IfStatement.expression` is deprecated - use condition.expression
dsymbol\src\dsymbol\conversion\first.d(971,33): Deprecation: function `dparse.ast.IfStatement.expression` is deprecated - use condition.expression
common\src\dcd\common\messages.d(256,3): Deprecation: `return` statements cannot be in `scope(failure)` bodies.
common\src\dcd\common\messages.d(256,3):        Use try-catch blocks for this purpose