Specify Dependencies with JSON

[ryanmrichard]

Is your feature request related to a problem? Please describe.
Having dependency information embedded in CMakeLists.txt makes it hard to access outside the build system (e.g., during CI). Since 3.19 CMake has support for working with JSON, so we could allow users to provide a JSON file describing the dependencies and have CMaize populate the dependency information from the file. As an added benefit the CMakeLists.txt becomes shorter.

[ryanmrichard]

If we really want to go for broke how much of the build system can we specify in a JSON?

{
  "name" : "project name",
  "languages" : ["CXX", "C"],
  "options" : {
    "option0" : ["this is option 0", "default_value"],
    "option1" : ["this is option 1", "default_value"]
  },
  "dependencies" : {
    "dependency0" : { 
      "URL" : "www.internet.com",
      "VERSION" : "1.0.0",
      "CMAKE_ARGS" : {
        "arg0" : "value",
        "arg1" : "value"
      } 
    },
    "dependency1" : {}  
  },
  "targets" : {
      "target0" : {}
  },
  "package" : ["target0"]
}