OK try this...
Go here and download:
https://bitbucket.org/fmalpartida/new-liquidcrystal/downloads/
seems not all the libraries work with ATTINY.
Open file I2CIO.cpp
After line 34 insert the code below:
#if defined(AVR_ATtiny84) || (AVR_ATtiny2313)
#include "TinyWireM.h" // include this if ATtiny85 or ATtiny2313
#define Wire TinyWireM
#else
#include <Wire.h> // original lib include
#endif
#include <TinyWireM.h> // ATtiny I2C communication
#include <LiquidCrystal.I2C.h>
#define GPIO_ADDR 0x3F
LiquidCrystal_I2C lcd(GPIO_ADDR, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);
long secs = 0;
void setup()
{
lcd.begin(16, 2); // set up the LCD's number of columns and rows.
lcd.setBacklight(ON);
lcd.clear();
lcd.setCursor(0,0);
lcd.print("Hello World!");
}
void loop()
{
}