Fix potential crashes
 - some compilers have problems with using locally redeclared loop vars after an internal loop
 - fix ordering of conditional checks
When setting the field on a GuiInspectorField, check if the field  is null before setting the docs.
Fixed issue #256: "$pref::TS::smallestVisiblePixelSize doesn't work".
Fixed Box3F::overlap
changed Generator to T3D_Generator to prevent problems with newer php versions
Merge pull request #556 from camporter/mfield_null_check

When setting the field on a GuiInspectorField, check if the field is null before setting the docs
Merge pull request #570 from eightyeight/box3f-overlap

Fixed Box3F::overlap
Merge pull request #563 from signmotion/smallestVisiblePixelSize-work

Fixed issue #256: "$pref::TS::smallestVisiblePixelSize doesn't work".
Merge pull request #580 from tdev/php_generator_fixes

fixes problems for newer php version
Merge pull request #547 from asmaloney/fix_potential_crashes

Fix potential crashes