introduce doxygen configuration

now it's possible to run doxygen tool to produce HTML documentation (reference and examples)
introduce unit-test VS solution

early draft version: supports http, json, dump, log, swab unit tests
Merge branch 'hotfix-1.0.1'
use FrameContent class as base for all binary frames (gateway and XBee)
split gateway API into API and Engine

API is responsible for IO operations (as a transceiver)
Engine is responsible for intent/layouts managements and binary<->JSON conversion
XBee gateway example

- gateway binary protocol implemented via XBee API
- xbee::Debug class to dump frame payloads
- command line arguments
introduce main constructor for cloud6::Notification
upgrade test solution to support examples

now it's possible to build examples from test solution too.
'xbee_gw' example renamed to 'zigbee_gw'
introduce ServerModule and SerialModule for the examples.

Some common functionality moved into separate classes:
  - basic_app::ServerModule which is used to register devices and poll for commands
  - basic_app::SerialModule which is used to open serial port
Application class is derived from these modules.

(need to synchronize documentation!)
update examples and doxygen documentation

- tools/crosstool-ng/raspberrypi/ configuration introduced
- "Getting started" page introduced
- directory structure on the main page
- new example page names
- Makefile for 'test' directory
update examples

- force 'terminated' flag, so we can check terminated() inside stop() method
- use named constants for various timeouts
- catch exceptions on command processing
- use cloud6::Notification main constructor where possible
- zigbee_gw: rename RemoteDevice to ZDevice
introduce Visual Studio 2008 Express solutions

new (2008 Express) solutions are located in 'vs-2008e' directories
previous (2010) solutions are located in 'vs-2010' directories
swab/h2le/h2be function overloads for signed integers

swab unit test updated - check for LE & BE conversions
hive::dump code review

overloads for signed integers
test-dump for integers
documentation updates
Makefile updates

- link boost.system as static library
- use explicit rules for examples

test-swab: avoid "break strict-aliasing rules" warning
logging: support for log file size limit

- support for log file size limit
- support for maximum number of backups
- test the custom format feature
- update documentation
start of websocket development (update HTTP unit)

- support for `ws` and `wss` URL schemes
- http::Connection meets AsyncReadStream and AsyncWriteStream requirements (to use with binary Transceiver)
- http::Client::send2() method reports the corresponding HTTP connection (will be used by websocket)
- http response by default doesn't expect response body, i.e. `rx_len` is zero
- base64 encoding and decoding functions
DeviceHive/binary.hpp moved to hive/binary.hpp
introduce WebSocket early draft implementation

support for Frames (control and non-control) and Messages
simple test for Frame formatting
simple echo-server test
hive::log updates

- rename Target::Stderr to Target::Stream to support both std::cerr and std::cout
- support for the minimum logging level for the targets
- individual minimum logging level for the Tie children
- support for custom log formats with printf-like syntax
- update "logging tools" page