Type conversions like `RecognizeIntegers` when storing to database

[Nick-Lucas]

https://github.com/Nick-Lucas/LimeBean/pull/3/commits/00f2324feac2c6737b78aaad29b368d7bc332b31

If the database will always re-convert any of our conversions back to the correct type of the field, we should only bother attempting conversions such as this when in FluidMode, and allow disabling of it in that situation. Need to research if this is the real behaviour on all DBMS's.

Right now we always convert to integers if possible, regardless of whether the field exists in the database, which seems a little inefficient.

There may be other cases like this which can be reviewed