vera: Introduce vera own skipToEndOfChar function(#179)

C and Vera, both parser used skipToEndOfChar function in get.c to
skip chars between single quotes. However, vera specialized logic
is hard-coded in skipToEndOfChar.

"Error parsing C/CPP files when certain element is present #179" spots
a bug trigger by the logic.

foo.c:

    char c[]={'o.'};

`c` should be picked as a tag. However, the logic recognized `o` as a
maker representing starting of octal value. As the result ctags didn't
picked `c` up.

In this change, I introduced a data type named 'cppCustomMethods'.
With this data type, the specialized logic is externalized from
get.c. Simplified version without the specialized logic of
skipToEndOfChar cane be used if the client code doesn't use the data
type.

This change itself is over-engineered but can be used as building block
for extending functions in get.c.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>