Add 'date' to rc.decltypes interpreted as a time

[pwaller]

This commit simply tries to parse things as a time if the decltype is specified as a "date".

I found some databases which aren't correctly interpreted if this isn't checked as well.

[coveralls]

Coverage remained the same when pulling ff0960b on pwaller:decltype-date into 1704ea5 on mattn:master.

[mattn]

This also? https://github.com/pwaller/go-sqlite3/blob/ff0960b999eb967d04346ca98a0c3be37c0f51a4/sqlite3.go#L477

[pwaller]

@mattn I don't know about that one, I haven't come across it in the wild. Do you know what the correct conversion is if the field type is "date" but the underlying storage is an "int" ?

[mattn]

This is convertion for date to unix epoc.

[pwaller]

Done, sorry for the delay, was on holiday - will respond more quickly again now.

[coveralls]

Coverage decreased (-0.13%) when pulling 764e046 on pwaller:decltype-date into 1704ea5 on mattn:master.

[mattn]

Thank you