SI-6675 Avoid spurious warning about pattern bind arity.

In 692372ce, we added a warning (under -Xlint) when binding
a `TupleN` in to a single pattern binder, which wasn't allowed
before 2.10.0, and more often than not represents a bug.

However, that warning overstretched, and warned even when
using a Tuple Pattern to bind to the elements of such a value.

This commit checks for this case, and avoids the spurious warnings.

A new test case is added for this case to go with the existing
test for SI-6675:

    $ ./tools/partest-ack 6675
    % tests-with-matching-paths      ...  3
    % tests-with-matching-code       ...  2
    # 3 tests to run.
    test/partest --show-diff --show-log                  \
      test/files/neg/t6675-old-patmat.scala              \
      test/files/neg/t6675.scala                         \
      test/files/pos/t6675.scala                         \
      ""

    Testing individual files
    testing: [...]/files/pos/t6675.scala                                  [  OK  ]

    Testing individual files
    testing: [...]/files/neg/t6675-old-patmat.scala                       [  OK  ]
    testing: [...]/files/neg/t6675.scala                                  [  OK  ]
    All of 3 tests were successful (elapsed time: 00:00:03)
SI-7355 Handle spaces in paths in Windows batch files.

Changed "%1%" and %2% to "%~1" and %~2 to allow spaces
in paths by surrounding quotes according to advice at:

  http://stackoverflow.com/questions/473117/pass-path-with-spaces-as-parameter-to-bat-file
  http://ss64.com/nt/syntax-args.html
Merge pull request #2435 from retronym/ticket/7355

SI-7355 Handle spaces in paths in Windows batch files.
Merge pull request #2420 from retronym/ticket/6675-2

SI-6675 Avoid spurious warning about pattern bind arity.
SI-6943 warn on value class miscomparison.

There's a very dangerous situation running around when you
combine universal equality with value classes:

  // All over your code
  val x = "abc"
  if (x == "abc") ...

  // Hey let's make x a value class
  val x = new ValueClass("abc")
  // Uh-oh

There was until now no warning when comparing a value class
with something else. Now there is.
Merge pull request #2444 from paulp/pr/value-class-cmp-warning

SI-6943 warn on value class miscomparison.