Custom runtime module errors (#3433)

* srml-system checks

* wip

* more modules compiles

* node-runtime checks

* build.sh passes

* include dispatch error in failed event

* revert some unnecessary changes

* refactor based on comments

* more compile error fixes

* avoid unnecessary into

* reorder code

* fixes some tests

* manually implement encode & decode to avoid i8 workaround

* more test fixes

* more fixes

* more error fixes

* Apply suggestions from code review

Co-Authored-By: Tomasz Drwięga <[email protected]>

* address comments

* test for DispatchError encoding

* tyep alias for democracy

* make error printable

* line width

* fix balances tests

* fix executive test

* fix system tests

* bump version

* ensure consistent method signature

* Apply suggestions from code review

Co-Authored-By: Gavin Wood <[email protected]>

* changes based on review

* Add issue number for TODOs

* fix

* line width

* fix test

* Update core/sr-primitives/src/lib.rs

Co-Authored-By: Bastian Köcher <[email protected]>

* Update core/sr-primitives/src/traits.rs

Co-Authored-By: Bastian Köcher <[email protected]>

* Update srml/council/src/motions.rs

Co-Authored-By: Bastian Köcher <[email protected]>

* Update srml/council/src/motions.rs

Co-Authored-By: Bastian Köcher <[email protected]>

* update based on review

* More concrete macro matching

* fix test build issue

* Update hex-literal dependency version. (#3141)

* Update hex-literal dep version.

* Update lock file.

* Start to rework the new error handling

* More work to get it back compiling

* Start to fix after master merge

* The great transaction error handling refactoring

* Make `decl_error` errors convertible to `&'static str`

* Make srml-executive build again

* Fix `sr-primitives` tests

* More fixes

* Last round of fix ups

* Fix build

* Fix build

* Apply suggestions from code review

Co-Authored-By: Tomasz Drwięga <[email protected]>

* Rename some stuff

* Fixes after master merge

* Adds `CheckBlockGasLimit` signed extension

* Remove debug stuff

* Fix srml-balances test

* Rename `InvalidIndex` to `CannotLookup`

* Remove weird generic parameters

* Rename function again

* Fix import

* Document the signed extension

* Change from `Into` to `From`

* Update srml/contracts/src/lib.rs

Co-Authored-By: Sergei Pepyakin <[email protected]>

* Fix compilation

* Update srml/contracts/src/lib.rs

Co-Authored-By: Tomasz Drwięga <[email protected]>

* Update core/sr-primitives/src/transaction_validity.rs

Co-Authored-By: Tomasz Drwięga <[email protected]>

* Remove unused code

* Fix compilation

* Some cleanups

* Fix compile errors

* Make `TransactionValidity` a `Result`

* Apply suggestions from code review

Co-Authored-By: Gavin Wood <[email protected]>

* Beautify the code a little bit and fix test

* Make `CannotLookup` an inherent error declared by `decl_error!`

* Adds some documentation

* Make `ApplyOutcome` a result

* Up the spec_version

* Apply suggestions from code review

Co-Authored-By: Gavin Wood <[email protected]>
Co-Authored-By: DemiMarie-parity <[email protected]>