Edje edit: improve state code generation.

Edje edit: improve state code generation.

Split function _edje_generate_source_of_state into
separated smallest functions, that represent generation
of source code for different blocks.
List of added internal functions:
  - _edje_generate_source_state_map
  - _edje_generate_source_state_box
  - _edje_generate_source_state_table
  - _edje_generate_source_state_image
  - _edje_generate_source_state_proxy
  - _edje_generate_source_state_relative

Add support collapse blocks, in cases when
block contain only one attribute.
For example:
next EDC code
  description { state: "default";
    {
      rel1 {
         relative: 0.5 0;
      }
    }

now will be replaced by:
  description { state: "default";
    {
       rel1.relative: 0.5 0;
    }