Problems with html generation for the documentation

[David Lucas]

For now, there is some problems with linear_code.py :

• unexpected indent at line 21
• non closure in a string block at line 26 in syndrome method. Seems to be related to the second block of examples (because if it is integrated in the first block, it passes the generation).

And there is some 'ascii' codec can't decode byte in concatenated_code.py and grs.py No clue about that one.