Remove dependency on error_chain (#277)

* Convert validation error

* Convert wasm_executor error

* Convert block evaluation error

* Convert collation errors and the compilation

* Remove error-chain dep from service

* Remove unused Result type

* Remove unused error variants

* Remove redundant intos

* Add missing comments

* Update validation/src/collation.rs

Co-Authored-By: thiolliere <[email protected]>

* Fix new error variant