Change getmininginfo errors field to warnings

Changes the errors field to warnings. To maintain compatibility,
the errors field is deprecated and enabled by starting bitcoind with
-deprecatedrpc=getmininginfo

test/functional/p2p-versionbits-warning.py

@@ -87,7 +87,7 @@ class VersionBitsWarningTest(BitcoinTestFramework):
         self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD + 1)
         # Check that we're not getting any versionbit-related errors in
         # get*info()
-        assert(not VB_PATTERN.match(self.nodes[0].getmininginfo()["errors"]))
+        assert(not VB_PATTERN.match(self.nodes[0].getmininginfo()["warnings"]))
         assert(not VB_PATTERN.match(self.nodes[0].getnetworkinfo()["warnings"]))
 
         # 3. Now build one period of blocks with >= VB_THRESHOLD blocks signaling
@@ -98,7 +98,7 @@ class VersionBitsWarningTest(BitcoinTestFramework):
         # have gotten a different alert due to more than 51/100 blocks
         # being of unexpected version.
         # Check that get*info() shows some kind of error.
-        assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getmininginfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getmininginfo()["warnings"])
         assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getnetworkinfo()["warnings"])
 
         # Mine a period worth of expected blocks so the generic block-version warning
@@ -113,7 +113,7 @@ class VersionBitsWarningTest(BitcoinTestFramework):
 
         # Connecting one block should be enough to generate an error.
         self.nodes[0].generate(1)
-        assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getmininginfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getmininginfo()["warnings"])
         assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getnetworkinfo()["warnings"])
         self.stop_nodes()
         self.test_versionbits_in_alert_file()