add if_match object comparing strings, floats and ints

add if_match object comparing strings, floats and ints

In general, argument types should match, but for combined long and
double usage the long is being converted to double before evaluation.

A few examples:
${if_match ${cpu} < 30}
${if_match "asdf" != "qwer"}
${if_match 0.5 < 0.50001}
${if_match 49.999 < 50}