If anybody want to experiment with and needs some guidance, please find below a step-by-step Install Guide for a Arduino 1.6.4 Portable environment. It's including also ESP8266 packages, ready for programming your ESP Boards.
INSTALL GUIDE:
FIRST RUN - Blinky time 
Detailed step-by-step guide with pictures: ESP8266 + Arduino IDE 1.6.4 Portable - Full Install step-by-step Guide