Sqlmap

* Added module for MS SQL Server;
* Strongly improved MySQL dbms active fingerprint and added MySQL comment injection check;
* Added PostgreSQL dbms active fingerprint;
* Added support for string match (`--string`);
* Added support for UNION check (`--union-check`);
* Removed duplicated code, delegated most of features to the engine in common.py and option.py;
* Added support for `--data` command line argument to pass the string for POST requests;
* Added encodeParams() method to encode url parameters before making http request;
* Many bug fixes;
* Rewritten documentation files;
* Complete code restyling.

* complete refactor of entire program;
* added TODO and THANKS files;
* added some papers references in README file;
* moved headers to user-agents.txt, now -f parameter specifies a file (user-agents.txt) and randomize the selection of User-Agent header;
* strongly improved program plugins (mysqlmap.py and postgres.py), major enhancements: * improved active mysql fingerprint check_dbms(); * improved enumeration functions for both databases; * minor changes in the unescape() functions;
* replaced old inference algorithm with a new bisection algorithm.
* reviewed command line parameters, now with -p it's possible to specify the parameter you know it's vulnerable to sql injection, this way the script won't perform the sql injection checks itself; removed the TOKEN parameter;
* improved Common class, adding support for http proxy and http post method in hash_page;
* added OptionCheck class in option.py which performs all needed checks on command line parameters and values;
* added InjectionCheck class in injection.py which performs check on url stability, dynamics of parameters and injection on dynamic url parameters;
* improved output methods in dump.py;
* layout enhancement on main program file (sqlmap.py), adapted to call new option/injection classes and improvements on catching of exceptions.