XSS is not available in python package

Python wrapper (compiled for linux and python 2.7) does not expose `xss` method
```shell
>>> import libinjection
>>> libinjection.xss
Traceback (most recent call last):
File "", line 1, in
AttributeError: 'module' object has no attribute 'xss'
>>> dir(libinjection)
['FLAG_NONE', 'FLAG_QUOTE_DOUBLE', 'FLAG_QUOTE_NONE', 'FLAG_QUOTE_SINGLE', 'FLAG_SQL_ANSI', 'FLAG_SQL_MYSQL', 'LOOKUP_FINGERPRINT', 'LOOKUP_OPERATOR', 'LOOKUP_TYPE', 'LOOKUP_WORD', 'SWIG_PyInstanceMethod_New', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '__path__', 'is_sqli', 'libinjection', 'sqli', 'sqli_blacklist', 'sqli_callback', 'sqli_check_fingerprint', 'sqli_fingerprint', 'sqli_fold', 'sqli_get_token', 'sqli_init', 'sqli_lookup_word', 'sqli_not_whitelist', 'sqli_reset', 'sqli_state', 'sqli_token', 'sqli_tokenize', 'version']
```