Corrected all asserts with exit(EXIT_FAILURE)

[vickvey]

• assert.h should not be in production code.
• We are already printing the error messages but was using assert() as a break point to break the program in between, this might not be a great idea as assert also exposes the source variables in the console or so.
• I replaced it with exit(EXIT_FAILURE) as it is more robust way of exiting the program, It helps us in hiding the source variables info which were exposed in assert() and gives us a robust way of exiting a program.