and make it possible to configure it in the settings.
Split up S60Devices up into a class hierarchy and implement
the Autodetected Windows case and the manually configured
Linux case separately for code clarity. Same with the settings
widgets.
Reviewed-by: con

Some categories do not have icons yet, unfortunately.

- Autodetect SDK by environment variable EPOCROOT and qt directory
below.
- Environment::appendOrSet/prependOrSet: Avoid duplicate entries
- Rename toolchain enumeration value
- Adapt S60ToolChainMixin to new GnuPoc setup, provide routines for
  all required variables.
- RVCTToolChain: Make RVCT detection smarter (Check for RVCT<v1><v2>BIN
  variable). Set all required variables in case of RVCTToolChain/GnuPoc
- QtVersionManager: Detect toolchain and Qt version properly, make S60
  device run config accept toolchain.
- Modify S60DeviceRunControl to execute 'make sis'
- Modify S60Devices::detectQt...() to check for Qt installed into SDK
  first and symlink as fallback.

  * Use id() for methods returning a string used to represent
    some type of object.
  * Use displayName() for strings that are meant to be user
    visible.
  * Quieten some warnings while touching the files anyway.
  * Move Factories to their products in the plugins where that
    was not done before.

Reviewed-by: dt

Separate category and trCategory and introduce sorting characters
to the categories. Same for id/name.

Display the error in a label of the preferences page.
Reviewed-by: con

- Introduce a communications device type flag, add stubs for
  Bluetooth to serialdevicelister and pass the device type
  in new struct CommunicationDevice along to run configuration
  and debugger start parameters (overriding the debugger settings).
- Give the s60devices::Device a tooltip in the settings page