added explicit converter between ID types of same size

git-svn-id: http://svn.code.sf.net/p/retroshare/code/branches/v0.6-IdCleaning@7170 b45a01b8-16f6-495d-af2f-9b41ad6348cc
removed circular dependencies between includes

git-svn-id: http://svn.code.sf.net/p/retroshare/code/branches/v0.6-IdCleaning@7171 b45a01b8-16f6-495d-af2f-9b41ad6348cc
fixed compilation

git-svn-id: http://svn.code.sf.net/p/retroshare/code/branches/v0.6-IdCleaning@7173 b45a01b8-16f6-495d-af2f-9b41ad6348cc
comment out some unused types/structs

git-svn-id: http://svn.code.sf.net/p/retroshare/code/branches/v0.6-IdCleaning@7174 b45a01b8-16f6-495d-af2f-9b41ad6348cc