The widely accepted is 12 pairs of cranial nerves. If someone wants to add some more to the list, it will look like this one:

0 - The nervus teminalis
I - Olfactory
II - Optic
III - Oculomotor
IV- Trochlear
V - Trigeminal
VI - Abducens
VII - Facial
VIII - Vestibulo-cochlear (Auditory)
IX - Glossopharyngeal
X - Vagus
XI - Accessory
XII - Hypoglossal
XIII - C1

So we can have 14 pairs of cranial nerves. The zeroth cranial nerve: Nervus terminalis and the thirteenth cranial nerve: C1

What will happen to the Cervical spinal nerves??

They can be renamed as Nuchal...so C2 will be N1 (Nuchal 1) and so on...So the remaining spinal nerves need not be renamed.