Mk/bsd.options.desc.mk: Add shared version control OPTIONS & descriptions

• Add CVS description
• Add DARCS description
• Add GIT description
• Add MERCURIAL description
• Add PERFORCE description
• Rename SVN to SUBVERSION

devel/anjuta:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE and OPTIONS_DEFAULT
• Change SUBVERSION_DESC to use the default description

devel/git:

• Rename OPTION P4 to PERFORCE
• Rename OPTION SVN to SUBVERSION
• Change PERFORCE_DESC to use the default description

devel/ocaml-opam:

• Rename OPTION HG to MERCURIAL
• Sort OPTIONS_DEFINE and OPTIONS_DEFAULT
• Change {DARCS,GIT,MERCURIAL}_DESC to use the default description

devel/thunar-vcs-plugin:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE
• Change GIT_DESC to use the default description

devel/viewvc-devel:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE, OPTIONS_DEFAULT and OPTIONS_SINGLE

net-mgmt/observium:

• Rename OPTION SVN to SUBVERSION

net-mgmt/rancid3:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_SINGLE_SCM
• Change {CVS,GIT,SUBVERSION}_DESC to use the default description

ports-mgmt/portshaker:

• Rename OPTION SVN to SUBVERSION
• Rename HG to MERCURIAL
• Sort OPTIONS_DEFINE
• Change {GIT,MERCURIAL}_DESC to use the default description

security/hydra:

• Rename OPTION SVN to SUBVERSION

security/medusa:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE

shells/scponly:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE
• Typo fix in SVNSERVE_DESC

www/trac-devel:

• Rename OPTION SVN to SUBVERSION
• Sort OPTIONS_DEFINE, OPTIONS_DEFAULT and OPTIONS_MULTI_DATABASE
• Change {GIT,SUBVERSION}_DESC to use the default description

Reviewed by: koobs, adamw, dvl, garga, hannes_mehnert.org, rm, dbaio, romain
Approved by: koobs (ports, mentor)
Differential Revision: https://reviews.freebsd.org/D17459
MFH: No (OPTION description updates)