[BUG] Multiple typecasting issues in this library.

[yashmulgaonkar]

This is a very poorly written library, with blatant errors.

There are multiple instances where variables are incorrectly typecasted.
Durations are requested in milliseconds, but are typecasted as uint8_t.

Here is one such example:
tOn requested as milliseconds:
void SX1509::blink(uint8_t pin, unsigned long tOn, unsigned long tOff, uint8_t onIntensity, uint8_t offIntensity)

Later typecasted as uint8_t:
void SX1509::setupBlink(uint8_t pin, uint8_t tOn, uint8_t tOff, uint8_t onIntensity, uint8_t offIntensity, uint8_t tRise, uint8_t tFall, bool log)

[yashmulgaonkar]

Looks like this was caused by what looks like a careless "replace all" operation in this commit:
3ba49b6

[nseidle]

You're probably right. Maybe you can fix it. PRs are always welcome.

[gb-123-git]

@yashmulgaonkar
I went through the earlier commits. I don't think this has been caused by "replace all". (Disclaimer: It ("replace all") was not done by me btw)

The code for void SX1509::blink & void SX1509::setupBlink seems to be different. In void SX1509::setupBlink, remarks are specifically mentioning that tOn for this method should not be more than 5 bits.

There seems to be some other problem.