move dependencies to use pkg

cmake/pkg.cmake

@@ -0,0 +1,40 @@
+set(pkg-bin "${CMAKE_BINARY_DIR}/dl/pkg")
+if (${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
+  set(pkg-url "pkg")
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL "Windows")
+  set(pkg-url "pkg.exe")
+elseif (${CMAKE_SYSTEM_NAME} STREQUAL "Darwin")
+  set(pkg-url "pkgosx")
+else()
+  message(STATUS "Not downloading pkg tool. Using pkg from PATH.")
+  set(pkg-bin "pkg")
+endif()
+
+if (pkg-url)
+  if (NOT EXISTS ${pkg-bin})
+    message(STATUS "Downloading pkg binary from https://github.com/motis-project/pkg/releases/latest/download/${pkg-url}")
+    file(DOWNLOAD "https://github.com/motis-project/pkg/releases/latest/download/${pkg-url}" ${pkg-bin})
+    if (UNIX)
+      execute_process(COMMAND chmod +x ${pkg-bin})
+    endif()
+  else()
+    message(STATUS "Pkg binary located in project.")
+  endif()
+endif()
+
+message(STATUS "${pkg-bin} -l -h -f")
+execute_process(
+  COMMAND ${pkg-bin} -l -h -f
+  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+)
+
+if (IS_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/deps")
+  add_subdirectory(deps)
+endif()
+
+set_property(
+  DIRECTORY
+  APPEND
+  PROPERTY CMAKE_CONFIGURE_DEPENDS
+  "${CMAKE_CURRENT_SOURCE_DIR}/.pkg"
+)