Building ROS package depending on Open3D fails

**Describe the bug**
Trying to build a ROS package depending on Open3D. Open3d is built from source and installed on non root location. (e.g. ~/user/git/Open3d/install

Being a ROS package, CMakeLists.txt contains `find_package(catkin REQUIRED COMPONENTS roscpp)` and also `find_package(Open3D REQUIRED)`.

If i run, `catkin build` i get the error
```
Could not find a package configuration file provided by "Open3D" with any
of the following names:

Open3DConfig.cmake
open3d-config.cmake
```
as expected.

If i then run `catkin build -DCMAKE_PREFIX_PATH="~/git/Open3D/install/lib/cmake` i get the error
```
Could not find a package configuration file provided by "CUDAToolkit" with
any of the following names:

CUDAToolkitConfig.cmake
cudatoolkit-config.cmake
```
which is NOT expected.

Finally, if i `catkin build -DCMAKE_PREFIX_PATH="~/git/Open3D/install/lib/cmake` after a complete deletion of `devel`, `install` folders (`catkin clean`), i get the error
```
Could not find a package configuration file provided by "catkin" with any
of the following names:

catkinConfig.cmake
catkin-config.cmake
```
which is not at all expected. Something probably messes up paths.

**To Reproduce**
Check abobe

**Expected behavior**
Projects depending on Open3D, can be built without erros and missing CMAKE config files.

**Environment (please complete the following information):**

- Operating system: Ubuntu 18.04
- Python version: Python 2.7 (ROS Melodic doesnt support 3)
- Open3D version: master branch
- Is this remote workstation?: no
- How did you install Open3D?: build from source
- Compiler version (if built from source): gcc 7.5

**Additional context**
Add any other context about the problem here.