Generate N test cases from Unit

[jeissonh]

When Player Solution is executed (Run button pressed):

For each nn of 'NN' test cases in Unit:

• [x] Copy input text to a $PLAYER_SOLUTION/bn_nn_input.txt file.
• [x] If test case has an expected output, copy it to a $PLAYER_SOLUTION/bn_nn_output_ex.txt file.
• [ ] If test case does not have an expected output and it has a least one standard generator, build the generator and generate the corresponding expected output. # Pending issue
• [x] If test case has expected error output, copy it to $PLAYER_SOLUTION/bn_nn_error_ex.txt.

If Unit has at least one generator:

• [x] Choose a random rr generator
• [x] Copy the source code of the generator to a file $PLAYER_SOLUTION/bn_gen_rr.c[pp]. Extension must be assigned according to the programming language of the generator.
• [x] Compile the generated file, and get an executable
• [x] Get the default-run attribute of the generator, lets name it MM
• [x] For each mm in MM, create the test case NN + mm depending on the type of generator. See examples below.
• [x] Store the number of generated test cases in player solution. It will required later by UnitPlayingScene to show the number of test cases to pass.

Standard generator:

/ps/bn_gen_01 04 09 > /ps/bn_04_input.txt 2> /ps/bn_04_args.txt
/ps/bn_sol_01 `< /ps/bn_04_args.txt` < /ps/bn_04_input.txt > /ps/bn_04_output_ex.txt 2> /ps/bn_04_error_ex.txt

File generator:

/ps/bn_gen_02 04 09 /ps/bn_05_input.txt /ps/bn_05_output_ex.txt /ps/bn_05_error_ex.txt /ps/bn_05_args.txt 

Notice standard-generator requires a solution element. #Issue pending

[jeissonh]

Missing output in botnu files is currently discouraged. Everything else is implemented.