Added bit banged serial

[9903286]

I've attempted to implement softwareserial into pigpioj and it seems i was successful, please check my code and see if i did anything weird considering this is my first time with JNI, C, makefiles and such.

From what i can see everything is working as intended, so i've also added a class called "PigpioTestBBSerial.java" in "uk.pigpioj.test" that gave me this output when i ran it:
https://pastebin.com/yk1fTkrS

(Simple to try yourself: Just change the pins in the java class and connect them together, then run the main function)

[mattjlewis]

Excellent, I'll take a look this weekend!

[9903286]

After running it for a while, i got
java: malloc.c:2406: sysmalloc: Assertion (old_top == initial_top (av) && old_size == 0) || ((unsigned long) (old_size) >= MINSIZE && prev_inuse (old_top) && ((unsigned long) old_end & (pagesize - 1)) == 0) failed.
Not sure what this means, but it seems to maybe be a memory leak caused by char *buf = (char*) malloc(maxSize); on line 34 in uk_pigpioj_PigpioBitBangSerial.c, not sure how to fix this.

[9903286]

Added the free() function to my malloc variable, seems to be working now, gonna run it for a while more tough.
EDIT: Been running it for 2+ hours now, seems to be fixed.