[test/wild] Summarize failures at the top level, in text and HTML.

The text can be used as a starting point for --not-shell and --not-osh.

- Write version text, like test/spec.sh does.
  - Extracted a function into test/common.sh and added an include guard.
- Add flags, as well as explicit input and output directories

test/common.sh

@@ -1,7 +1,12 @@
#!/bin/bash
#
# Usage:
#   ./common.sh <function name>
#   source test/common.sh

# Include guard.
test -n "${__TEST_COMMON_SH:-}" && return
readonly __TEST_COMMON_SH=1


# TODO: Remove/rename this.  The release process might use the release binary
# instead of this dev binary.  test/spec.sh already has its own scheme.
@@ -91,6 +96,20 @@ run-other-suite-for-release() {
  fi
}

date-and-git-info() {
  date
  echo

  if test -d .git; then
    local branch=$(git rev-parse --abbrev-ref HEAD)
    local hash=$(git rev-parse $branch)
    echo "oil repo: $hash on branch $branch"
  else
    echo "(not running from git repository)"
  fi
  echo
}

if test "$(basename $0)" = 'common.sh'; then
  "$@"
fi