V2.0.2:
+ added french language.
+ fixed a crash at donate section after returning from an ad.
+ added some hardcoded text to strings.
+ stop flash when a volume button is pressed when receiving a call
+ removed unnecessary libraries.
+ option to flash only if screen is off (at preferences->Operation Mode).
+ fixed flashing during viber call.
Merge branch 'master' of https://github.com/spirosbond/CallerFlashlight