Commits for larrym

v260_preview2 to v260_base (2011-11-22 to 2011-12-06) v260

• add tdbSetCartVisibility and use in hgTracks to fix #1666
  • src/hg/hgTracks/hgTracks.c - lines changed 9, context: html, text, full: html, text
  • src/hg/inc/cart.h - lines changed 2, context: html, text, full: html, text
  • src/hg/inc/trackDb.h - lines changed 9, context: html, text, full: html, text
  • src/hg/lib/trackDbCustom.c - lines changed 23, context: html, text, full: html, text
• cache NULLs in cvTermHash to avoid repeated lookups (part of attempt to speedup hgFileUi)
  • src/hg/lib/cv.c - lines changed 7, context: html, text, full: html, text