Allow strings of floats in geodist

[cappadaan]

This

(GEODIST(latitude, longitude, '0.905100348415', '0.10063376480782') / 1000) AS distance

gives

parse error: geodist() arguments can not be string

It would be very useful and more flexible to allow floats with quotes in queries. PDO has no float type, so a string has to be used which causes the parse error.