This commit brings the unmaintained go-difflib back to working
condition:

  - Add go.mod with Go 1.16 support and updated module path
  - Fix test compilation errors (rename example functions)
  - Update installation instructions for modern Go

  The library now works with `go get
github.com/codinganovel/go-difflib/difflib`
  and compiles/tests successfully with current Go versions.

- Remove broken address comparison in SetSeq1/SetSeq2 functions
  - Functions now properly clear cache instead of failing optimization
  - Update repository references in README from pmezard to codinganovel

- Add IsLineJunk/IsCharacterJunk
- Tests: round‑trip, intraline; examples added
- README: new features, examples, API notes
- TO-DO: progress and next steps
- go fmt/vet clean

- NDiff options and API:
    - Added NDiffOptions with LineJunk, CharJunk, and Intraline.
    - Added NDiffWith(a, b []string, opts NDiffOptions)
[]string.
    - Behavior:
    - `Intraline: true` → adds “? ” guide lines (uses `Differ`
under the hood).
    - `Intraline: false` → same output style as `NDiff`, but
honors `LineJunk` for matching.
    - `CharJunk`: defaults to `IsCharacterJunk` when intraline
is on and `CharJunk` is nil.

- Differ improvements:
    - Differ.Compare now honors LineJunk by using
NewMatcherWithJunk.
    - Intraline builder now respects CharJunk via a new helper:
    - Replaced `buildIntralineTags` with
`buildIntralineTagsWith(aline, bline string, charJunk func(rune)
bool)`.
    - Uses `NewMatcherWithJunk` on character sequences with a
rune-aware junk adapter.

- Imports:
    - Added unicode/utf8 for safe rune decoding in intraline
junk adapter.

- Existing NDiff(a, b []string) remains unchanged for backward
compatibility.
- Differ still has simple replace pairing (not the full
_fancy_replace yet), but now respects junk filters as requested.
- If you want, I can proceed next to add more table-driven
tests around junk filters and multi-line replacements, or start
_fancy_replace work.

- Byte adapters:
    - Unified: WriteUnifiedDiffBytes, GetUnifiedDiffBytes, with
UnifiedDiffBytes struct.
    - Context: WriteContextDiffBytes, GetContextDiffBytes, with
ContextDiffBytes (alias of bytes struct).
    - Behavior: split on '\n' via SplitLinesBytes, convert lines
to strings without decoding, delegate to existing string-based
writers, return bytes.
- Tests/Examples:
    - ExampleGetUnifiedDiffBytes mirrors the unified example
using bytes.
    - ASCII parity:
TestUnifiedDiffBytes_EqualsStringUnified_ASCII,
TestContextDiffBytes_EqualsStringContext_ASCII.
    - Binary safety: TestUnifiedDiffBytes_BinarySafety,
TestContextDiffBytes_BinarySafety (handles NUL and 0xFF, no
panics).

Files Changed

- difflib/difflib.go: added UnifiedDiffBytes,
WriteUnifiedDiffBytes, GetUnifiedDiffBytes, ContextDiffBytes,
WriteContextDiffBytes, GetContextDiffBytes.
- difflib/difflib_test.go: added example and tests.
- TO-DO.md: marked unified/context byte adapters as done.

- README updates:
    - Added NDiffWith, NDiffBytes, Unified/Context byte adapters
with examples.
    - Clarified Differ now honors LineJunk/CharJunk and provides
intraline hints.
    - Kept NDiff as a simple, stable API; pointed to NDiffWith
for intraline.
    - Added notes on byte safety and remaining HtmlDiff work.
    - Added notes on byte safety and remaining HtmlDiff work.
-
New tests:
    - NDiffBytes binary safety: ensures no intraline hints and
non-empty output with NUL bytes.
    - Unified/Context bytes: parity with string versions and
binary-safety (NUL and 0xFF) already included.

probably doesn't work, its 12:30 at night, ill double check it Tomorrow.