bugfix: indentation facade was undone by saving

Had to implement a deep copy for textbuffers.

	modified:   src/fileaccessor.rb
	modified:   src/textbuffer.rb
bugfix: indentchar issues

Needs testing.

	modified:   src/fileaccessor.rb
	modified:   src/filebuffer.rb
release 0.4.6

Mostly bugfixes.

	modified:   HISTORY.md
	modified:   doc/jedi.1
	modified:   doc/make_doc.sh
	modified:   make_jedi.rb