2.10 released

Mostly minor bug fixes.

- Significantly improved installation instructions in README.
- Renamed "Session" menu to "VM" as that makes more sense.
- Implemented RFE 508: source view line highlighter color is now
  customizable via the preferences dialog.
- Fixed bug 621: explained in "Classes" help section about multiple
  instances of the same class in the class tree.
- Fixed bug 622: changing the classpath or sourcepath will force the
  debugger to find source files in their new location the next time
  they are requested using a class name.
- Fixed bug 625: editing the classpath and sourcepath elements is now
  easier with a new Modify button and a dialog for editing the path
  entry. Additionally, the classpath editing dialog is now accessible
  while the session is active (although editing is still disallowed).
- Fixed bug 637: scroll the source view horizontally if needed to
  show matching text when searching.
- Fixed bug 638: documented slash escape sequences in the command
  parser; useful for treating special characters as normal.
- Fixed bug 643: locals panel would blink for each single-step event.
- Fixed bug 650: source view threw index out of bounds exception
  when evaluating text under mouse.
- Fixed bug 655: renamed the "session" menu items in the File menu
  so their purpose is more obvious.
- Fixed bug 659: changed upgrading message to say "2.x" instead of
  "2.0" since an upgrade could be directly from 1.x to 2.x.
- Fixed bug 661: source views are reloaded when the refresh action is
  invoked, useful when code may be changed during debugging.

enjoy

nathan