* Add proposal for supporting big transactions
* account index program
* fix formatting
* review feedback
* Add cost changes section
* Add cost section and more attack details
* fix lint
* document metadata changes
* nit
* rpc details
* add index meta struct
* add additional proposal and chagne title
* rename proposal file
* rename to address map and rewrite tx format
* no more appends, limit mapping size to 256
* update dos section
* add note about readonly
* restructure message to use enum
* cleanup
