top: exploit new linux-4.5 resident memory enhancement

top: exploit new linux-4.5 resident memory enhancement

Since support already exists in the newlib branch this
represents an equivalent master branch implementation,
and this commit message is shared with 2 more patches.

Beginning with linux-4.5, the following new fields are
being added under that /proc/<pid>/status pseudo file:
 . RssAnon - size of resident anonymous memory
 . RssFile - size of resident file mappings
 . RssShmem - size of resident shared memory

p.s. Locked resident memory support was also added but
isn't directly related to the kernel 4.5 enhancements.

p.p.s. Archlinux, Debian-stretch and Fedora-23 already
are currently using a 4.5 linux kernel (as of 6/2/16).

Signed-off-by: Jim Warner <james.warner@comcast.net>