feat(dap): Added debugger from cpptools

Added:
  - OpenDebugAD7 from [vscode-cpptools](https://github.com/microsoft/vscode-cpptools)

It works better with `nvim-dap-ui`. With GDB you have to wait for stdout
flush to see program output, the output is in the repl instead of the
console, etc. The VSCode debugger doesn't have such issues.

nvim/ftplugin/c.lua

@@ -35,20 +35,16 @@ dap.adapters.gdb = {
   args = { "-i", "dap" }
 }
 
+dap.adapters.cppdbg = {
+  id = 'cppdbg',
+  type = 'executable',
+  command = 'OpenDebugAD7',
+}
+
 dap.configurations.c = {
-  -- {
-  --   name = "Launch",
-  --   type = "gdb",
-  --   request = "launch",
-  --   program = function()
-  --     return vim.fn.input('Path to executable: ', vim.fn.getcwd() .. '/', 'file')
-  --   end,
-  --   cwd = "${workspaceFolder}",
-  --   stopAtBeginningOfMainSubprogram = false,
-  -- },
   {
     name = "Launch an executable",
-    type = "gdb",
+    type = "cppdbg",
     request = "launch",
     cwd = "${workspaceFolder}",
     program = function()
@@ -70,6 +66,6 @@ dap.configurations.c = {
           :find()
       end)
     end,
-    stopAtBeginningOfMainSubprogram = false,
+    stopAtBeginningOfMainSubprogram = true,
   },
 }