Add textobjects and indents to c and cpp (#1293)

Indentation of single line statements doesn't work, i.e.

  for (;;)<hit enter>
leads to
  for(;;)
  <cursor here>

Only blocks with curly braces are indented.

runtime/queries/cpp/textobjects.scm

@@ -0,0 +1,7 @@
+; inherits: c
+
+(lambda_expression
+  body: (_) @function.inside) @function.around
+
+(class_specifier
+  body: (_) @class.inside) @class.around