Merge branch 'libusb-update' into 'master'

Add multiple sources for Libusb download

See merge request iMSTK/iMSTK!245

CMake/External/External_Libusb.cmake

@@ -43,7 +43,7 @@ set(copy_libusb_pdb_command
 #-----------------------------------------------------------------------------
 include(imstkAddExternalProject)
 imstk_add_external_project( Libusb
-  URL http://downloads.sourceforge.net/project/libusb/libusb-1.0/libusb-1.0.21/libusb-1.0.21.7z
+  URL http://downloads.sourceforge.net/project/libusb/libusb-1.0/libusb-1.0.21/libusb-1.0.21.7z https://data.kitware.com/api/v1/item/59cbcefd8d777f7d33e9d9d7/download
   URL_MD5 7fbcf5580b8ffc88f3af6eddd638de9f
   DOWNLOAD_DIR ${Libusb_PREFIX}
   SOURCE_DIR ${Libusb_EXTRACT_DIR}

CMakeLists.txt

-cmake_minimum_required(VERSION 3.2)
+cmake_minimum_required(VERSION 3.9)
 project(iMSTK VERSION 0.0.1 LANGUAGES C CXX)
 
 if(UNIX AND NOT APPLE)

README.md

@@ -53,7 +53,7 @@ Designed more specifically for developers, the issue tracker allows developers t
 
 ## Prerequisites
 * Git
-* CMake 3.2 or higher
+* CMake 3.9 or higher
 
 ##### On Linux: