Travis CI and Documentation Generation improvements

* Use docker images from docker hub instead of building them on Travis
* Fix doxygen warnings for C/C++ Documentation
* Fix examples inclusion in documentation
* Modify Travis build matrix to include stages and additional jobs
* Update doxygen2jsdoc submodule
* Add doxyport submodule
* Generate documentation for each language in Travis
* Add sonar.java.binaries to sonar-scan.sh

Signed-off-by: Nicolas Oliver <dario.n.oliver@intel.com>

src/mraa.i

@@ -4,19 +4,6 @@
 %include std_string.i
 %include exception.i
 
-#ifdef DOXYGEN
-  //and doesn't seem to work correctly in SWIG's preprocessor
-  #ifdef SWIGPYTHON2
-        %include common_hpp_doc.i
-        %include gpio_class_doc.i
-        %include i2c_class_doc.i
-        %include pwm_class_doc.i
-        %include aio_class_doc.i
-        %include spi_class_doc.i
-        %include uart_class_doc.i
-    #endif
-#endif
-
 %{
     #include "common.hpp"
     #include "types.hpp"