[vala] (10 commits) Created branch emit-let

[Luca Bruno <lucabru src gnome org>]

The branch 'emit-let' was created.

Summary of new commits:

  edd1a0f... Fix capturing delegate parameters in async method.
  e3008e6... codegen: Add get_parameter_cvalue and load_parameter.
  9e71a0b... codegen: Add CCodeFunction.add_assignment convenience funct
  df2043a... codegen: Introduce emit_local and use store_local for visit
  bd04b28... codegen: Add convenience is_in_coroutine() function.
  81f07d5... codegen: Add not_in_coroutine convenience parameter to get 
  772757b... codegen: Rename append_array_size and get_array_sizes to *_
  3d130b5... codegen: Add get_field_cvalue and load_field.
  26a3e23... codegen: Use get_field_cvalue to unref fields.
  33a5da3... codegen: Add convenience load_this_parameter method.