Unable to compile sketch SoftwareSerialexample after loading esp8266 package

I have downloaded IDE 1.6.5 and compiled the sketch SoftwareSerialexample successfully which is under
"File > Examples" menu. Once I installed the package esp8266 by ESP8266 community and set the board to Generic ESP8266 Module, I am not able to see the library SoftwareSeriale and unable to compile the sketch SoftwareSerial example. I am getting the following error.

SoftwareSerialExample.ino:28:28: fatal error: SoftwareSerial.h: No such file or directory
compilation terminated.
Error compiling.

The build process is not including the library SoftwareSerial.

If I remove the package esp8266 then I am able to compile the sketch successfully and I see the following line in the build process.

Using library SoftwareSerial in folder: D:\ESP8266\Arduino\arduino-1.6.5-r2\hardware\arduino\avr\libraries\SoftwareSerial

I am new to Arduino and I am not sure how to fix this issue. Thanks.

I was also having the same issue, I think the sample code is supposed to be loaded on an Arduino and not ESP8266. Looking at the image https://github.com/tuanpmt/espduino/blob/master/fritzing/espdruino_bb.png?raw=true he does have an Arduino wired up.