ide, installer: (#718) New Project/Open Dialog: Defaulting to HOME rather than workin...

ide, installer: (#718) New Project/Open Dialog: Defaulting to HOME rather than working directory
- On Windows, the installer would set up these to point to the Samples folder on first run,
  but on Linux or if samples were opted out the current working directory could be very confusing.
- We should avoid using the current working directory as much as possible, as the IDE might be started
  from any directory at the command line. I believe the only remaining place where the cwd is used
  is for the Find in Files dialog default 'Search in' directory. The cwd is also changed and then
  restored when invoking the debugger or compiler.