Add TimeOffsets helper class

This helper class is an alternative to CMedianFilter, but without a
lot of the special logic and exceptions that we needed while it was
still used for consensus.

src/Makefile.test.include

@@ -152,6 +152,7 @@ BITCOIN_TESTS =\
   test/sync_tests.cpp \
   test/system_tests.cpp \
   test/timedata_tests.cpp \
+  test/timeoffsets_tests.cpp \
   test/torcontrol_tests.cpp \
   test/transaction_tests.cpp \
   test/translation_tests.cpp \
@@ -382,6 +383,7 @@ test_fuzz_fuzz_SOURCES = \
  test/fuzz/strprintf.cpp \
  test/fuzz/system.cpp \
  test/fuzz/timedata.cpp \
+ test/fuzz/timeoffsets.cpp \
  test/fuzz/torcontrol.cpp \
  test/fuzz/transaction.cpp \
  test/fuzz/tx_in.cpp \