include: Spelling fixes

Correct typos of the following word families:

activities
forward
occurs
unprepared
association
compress
extracted
doubly
callback
prometheus
underlying
keyframe
continue
convenience
calculates
ignorepattern
determine
subscribers
subsystem
synthetic
applies
example
manager
established
result
microseconds
occurrences
unsuccessful
accommodates
related
signifying
unsubscribe
greater
fastforward
itself
unregistering
using
translator
sorcery
implementation
serializers
asynchronous
unknowingly
initialization
determining
category
these
persistent
propagate
outputted
string
allocated
decremented
second
cacheability
destructor
impaired
decrypted
relies
signaling
based
suspended
retrieved
functions
search
auth
considered

ASTERISK-29714

Change-Id: I542ce887a16603f886a915920d5710d4a0a1358d