thread local chain type vs global chain type (#3327)

* Introduce GLOBAL_CHAIN_TYPE and make CHAIN_TYPE thread_local.
This makes testing more explicit and significantly more robust.

* set_local_chain_type() in tests

* cleanup - weird

* get pool tests working with explicit local chain_type config

* core tests working with explicit local chain_type

* p2p tests working with explicit local chain_type

* store tests working

* cleanup, feedback

store/tests/lmdb.rs

@@ -12,11 +12,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use grin_core as core;
 use grin_store as store;
 use grin_util as util;
 
-use grin_core::ser::{self, Readable, Reader, Writeable, Writer};
-
+use crate::core::global;
+use crate::core::ser::{self, Readable, Reader, Writeable, Writer};
 use std::fs;
 
 const WRITE_CHUNK_SIZE: usize = 20;
@@ -59,6 +60,7 @@ fn clean_output_dir(test_dir: &str) {
 }
 
 fn setup(test_dir: &str) {
+	global::set_local_chain_type(global::ChainTypes::Mainnet);
 	util::init_test_logger();
 	clean_output_dir(test_dir);
 }