Deploy Template - Validate the existence of an Immutable Storage Section

[YaronWittenstein]

To simplify significantly the implementation of the Immutable Storage, I suggest enforcing these rules upon each Template:

• Each Template must have Storage Layout Section #0. Its usage is to describe the Immutable Storage of each Account. If there is no Immutable Storage then the Storage Layout will be empty (but it'll still exist).

• There'll be exactly one Storage Layout Section targeting the Immutable Storage of each future Account spawned out of this Template.

This issue extends the code under Runtime::validate_deploy to assert the above

svm/crates/runtime/src/runtime/runtime.rs

Line 521 in 6edb73d

pub fn validate_deploy(&self, message: &[u8]) -> std::result::Result<(), ValidateError> {