AqBanking

Started simplifying BUILD process.

- no longer need to create symlinks
- started setting explicit paths to include directives
- moved some code files from previous "types" folder to "types2"
- moved some files from "backendsupport" to "dialogs"
- removed "types"
- renamed "types2" to "types"
- moved "system.h" and "version.h" to "aqbanking/"

These changes mean that include directives in programs need to be more
specific, e.g. instead of
"#include <aqbanking/transactions.h>"
use
"#include <aqbanking/types/transactions.h>"