Include polkadot version in artifact path (#1828)

closes #695

Could potentially be helpful to preserving caches when applicable, as
discussed in #685

kusama address: FvpsvV1GQAAbwqX6oyRjemgdKV11QU5bXsMg9xsonD1FLGK

polkadot/node/primitives/src/lib.rs

@@ -53,6 +53,13 @@ pub use disputes::{
 	ValidDisputeVote, ACTIVE_DURATION_SECS,
 };
 
+/// The current node version, which takes the basic SemVer form `<major>.<minor>.<patch>`.
+/// In general, minor should be bumped on every release while major or patch releases are
+/// relatively rare.
+///
+/// The associated worker binaries should use the same version as the node that spawns them.
+pub const NODE_VERSION: &'static str = "1.1.0";
+
 // For a 16-ary Merkle Prefix Trie, we can expect at most 16 32-byte hashes per node
 // plus some overhead:
 // header 1 + bitmap 2 + max partial_key 8 + children 16 * (32 + len 1) + value 32 + value len 1