update INSTALL and README + friends for the everywhere package

At the moment we have in the root of qt-everywhere-opensource-src-4.6.0:

INSTALL
README
README.s60
README.wince

The problem with this is: First, we have duplicate information between these .txt files and our HTML version of our install docs. Second, we're making S60 and Windows CE into special cases. Third, there seems to be no documentation for Qt for Embedded Linux / Maemo in the root.

Here is what needs to happen to fix this:

• README.s60 and README.wince should be deleted, and README and INSTALL should be made generic.
• INSTALL needs to refer to the platforms install links found at file:///C:/Qt/qt-everywhere-opensource-src-4.6.0/doc/html/installation.html
• README needs to update "INSTALLING Qt" to reflect the above
• README needs to update "DEMOS AND EXAMPLES" to mention fluidlauncher for the embedded/mobile platforms
• README needs to update "HOW TO REPORT A BUG" with new task tracker link, and also mention how to contribute through gitorious