Added read-only mode to SQLite3 and two new methods to MySQL fetch

Added read-only mode to SQLite3 and two new methods to MySQL fetch.
This release also added the library opening functions to luasql.h in order to ease the initialization process in C applications.

Added seek method to MySQL driver

Added seek method to MySQL driver and bug-fix on ODBC driver number retrieval.

Some small improvements

v2.4.0

Updating current version number.

Minor corrections

v2.3.5

Rockspecs for new version.

Bug correction on Postgres driver

Bug correction on escape function of Postgres driver: strings bigger than the default buffer size are now correctly handled.

Bug correction on Postgres driver

Bug correction in the generation of error message after a failed connection.

v2.3.2

Bug correction on Postgres version

Compilation improvement on Postgres driver

Improvement on Postgres driver to work with compilers that don't provide dynamic array allocation.