Mk/**java.mk: Convert bsd.java.mk to USES

The following features have been added or changed:
- Instead of USE_JAVA use USES=java. This defaults to
  USES=java:build,run if NO_BUILD is undefined. Else it defaults to
  USES=java:run
- Instead of USE_ANT=yes use USES=java:ant which also implies
  USES=java:build
- Instead of JAVA_BUILD=yes use USES=java:build. Does not imply run or
  extract
- Instead of JAVA_EXTRACT=yes use USES=java:extract does not imply
  build or run
- Instead of JAVA_RUN=yes use USES=java:run does not imply extract or
  build
- Instead of USE_JAVA=<version> use USES=java and JAVA_VERSION=<version>

Approved by: mat (portmgr), glewis
Differential Revision:  https://reviews.freebsd.org/D48201

Remove WWW entries moved into port Makefiles

Commit b7f05445c00f has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.

This commit removes the WWW: lines of moved-over URLs from these
pkg-descr files.

Approved by:		portmgr (tcberner)

Add WWW entries to port Makefiles

It has been common practice to have one or more URLs at the end of the
ports' pkg-descr files, one per line and prefixed with "WWW:". These
URLs should point at a project website or other relevant resources.

Access to these URLs required processing of the pkg-descr files, and
they have often become stale over time. If more than one such URL was
present in a pkg-descr file, only the first one was tarnsfered into
the port INDEX, but for many ports only the last line did contain the
port specific URL to further information.

There have been several proposals to make a project URL available as
a macro in the ports' Makefiles, over time.

One more small cleanup, forgotten yesterday.
Reported by:	lwhsu

Remove # $FreeBSD$ from Makefiles.

Clean up after java/openjdk6 and java/openjdk6-jre removal

java/openjdk6 support was removed from Mk/bsd.java.mk (r512662) and
java/openjdk6 and java/openjdk6-jre were removed from the ports tree
(r512663).  Now this patch completely removes remaining stuff from the
ports tree.

PR:			241953 (exp-run)
Reviewed by:		glewis
Approved by:		portmgr (antoine)
Differential Revision:	https://reviews.freebsd.org/D22342

On amd64 adding DEFAULT_VERSIONS+=linux=c6 to /etc/make.conf made Linux
infrastructure ports (linux_base-c6 and linux-c6*) install i386 CentOS 6
packages.  Using c6_64 instead of c6 made them install mixed amd64/i386
CentOS 6 packages and allowed Linux application ports to install amd64
binaries when available.  The i386-only configuration was only useful for
users of x11/nvidia-driver* which didn't provide Linux amd64 emulation
until recently.

With x11/nvidia-driver* now supporting Linux amd64 there's no longer a
need for i386-only Linux on amd64.  Let DEFAULT_VERSIONS+=linux=c6 make
Linux infrastructure ports install mixed amd64/i386 CentOS 6 packages,
like c6_64 before, and remove support for c6_64 as a value.

Replace LINUX_ARCH with ARCH everywhere because they are always the same
now.

Expand DISTFILES in exists test.  DISTFILES isn't defined yet.

- Update WWW

Approved by:	portmgr blanket

[NEW PORT]: benchmarks/linux-vdbench: Command line disk I/O benchmark utility

Vdbench is a command line utility specifically created to help
engineers and customers generate disk I/O workloads to be used
for validating storage performance and storage data integrity.

WWW:
http://www.oracle.com/technetwork/server-storage/vdbench-downloads-1901681.html

Reviewed by:	koobs, mat
Approved by:	koobs (mentor)
Differential Revision:	https://reviews.freebsd.org/D17255