v1.1.0

### Releases v1.1.0

1. Restore cpp code besides Impl.h code to use if Multiple-Definition linker error.
2. Update examples.
3. Enhance README.

Author: khoih-prog

CONTRIBUTING.md

@@ -2,7 +2,7 @@
 
 ### Reporting Bugs
 
-Please report bugs in ESP8266TimerInterrupt if you find them.
+Please report bugs in [ESP8266TimerInterrupt Issues](https://github.com/khoih-prog/ESP8266TimerInterrupt/issues) if you find them.
 
 However, before reporting a bug please check through the following:
 
@@ -14,8 +14,8 @@ If you don't find anything, please [open a new issue](https://github.com/khoih-p
 
 Please ensure to specify the following:
 
-* Arduino IDE version (e.g. 1.8.11) or Platform.io version
-* `ESP8266` Core Version (e.g. ESP8266 core v2.6.3)
+* Arduino IDE version (e.g. 1.8.13) or Platform.io version
+* `ESP8266` Core Version (e.g. ESP8266 core v2.7.4)
 * Contextual information (e.g. what you were trying to achieve)
 * Simplest possible steps to reproduce
 * Anything that might be relevant in your opinion, such as:
@@ -26,10 +26,11 @@ Please ensure to specify the following:
 ### Example
 
 ```
-Arduino IDE version: 1.8.11
-ESP8266 Core Version 2.6.3
-OS: Ubuntu 16.04 LTS
-Linux Inspiron 4.4.0-170-generic #199-Ubuntu SMP Thu Nov 14 01:45:04 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
+Arduino IDE version: 1.8.13
+ESP8266 Core Version 2.7.4
+ESP8266_NODEMCU
+OS: Ubuntu 20.04 LTS
+Linux xy-Inspiron-3593 5.4.0-51-generic #56-Ubuntu SMP Mon Oct 5 14:28:49 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
 
 Context:
 I encountered a crash while trying to use the Timer Interrupt.