ADD URHO3D_PHYSICS AND URHO3D_NAVIGATION OPTIONS.
Merge branch 'more-options'
Add cmake options to Readme.txt [ci skip]
Merge branch 'master' of https://github.com/urho3d/Urho3D
Merge branch 'master' of https://github.com/urho3d/Urho3D
Merge branch 'master' of https://github.com/urho3d/Urho3D
Add draw debug geometry for tile map, fix tile map object position bug.
For Travis CI - switch CI build to use OS X build environment.