Rename is_bit_clear to bit_is_clear, is_bit_set to bit_is_set

[adamgreig]

Ugh, I know we just merged #109 but after using it for a couple of days I think it really should have been bit_is_set() rather than is_bit_set(). I'm happy with set_bit() and clear_bit() though, they seem natural:

usart3.cr3.dmat().set_bit();
while usart3.isr().tc().bit_is_clear() {}

if usart3.isr().ore().bit_is_set() {
    ...
}

As an added bonus, this way around we don't have to reserve the bit_set/bit_clear variant names, because it will no longer clash.

What do you think?

[japaric]

LGTM.

we don't have to reserve the bit_set/bit_clear variant names

👍

@whitequark Any opinion on this PR?

[whitequark]

@japaric No objection

[japaric]

@homunkulus r+

[homunkulus]

📌 Commit 718645c has been approved by japaric

[homunkulus]

⌛ Testing commit 718645c with merge 718645c...

[homunkulus]

☀️ Test successful - status-appveyor, status-travis
Approved by: japaric
Pushing 718645c to master...