Rename tools

Rename the user-visible tools to names that do not conflict with Qt 4 installations.

Recommendation from Simon on the mailing list is to prefix all tools with "qt5-". (e.g., qt5-qmake, qt5-moc, qt5-uic)

Tools affected are tools that are installed globally and run by the user, but not considered applications per se:

• Definitely: qmake
• Recommended:
  • moc
  • uic
  • rcc
  • designer
  • lconvert
  • lrelease
  • lupdate
  • qdbusxml2cpp
  • qdbuscpp2xml
  • qmlviewer
  • qmlscene
• Definitely not to be included: Creator, Assistant, Linguist, qdbus