Two issues with error message when using a bad PID string

[rwatson]

While mistyping a chericat command:

chericat -f tmp.db -p ./check.c18n

I ran into the following message:

chericat: Unable to obtain the vm map information from process 0, does cherciat have the right privilege?

There are two issues here: (1) Probably we should be using strtol() (or similar) rather than atoi() so that better error messages can reported -- it’s not 0, it’s a bad integer conversion and we shouldn’t have gotten this far; and (2) chericat is misspelled in the warning message.

[rwatson]

FYI, I noticed when reading the code that atoi() is used a fair amount in nearby code. On the whole, switching to using strtol() (or similar) to enable better error checking on values would likely be a good thing to do.

[psjm3]

Fixed in #27