Verify number of hashes for each block of entries (#6262)

* Verify number of hashes for each block of entries

* Fix blocktree processor tick check

* Rebase once more

ledger/src/block_error.rs

@@ -0,0 +1,15 @@
+#[derive(Debug, PartialEq)]
+pub enum BlockError {
+    /// Block entries hashes must all be valid
+    InvalidEntryHash,
+
+    /// Blocks can not have extra ticks or missing ticks
+    InvalidTickCount,
+
+    /// All ticks must contain the same number of hashes within a block
+    InvalidTickHashCount,
+
+    /// Blocks must end in a tick entry, trailing transaction entries are not allowed to guarantee
+    /// that each block has the same number of hashes
+    TrailingEntry,
+}