DOCS add Slackware install method
DOCS add Slackware install method

Signed-off-by: Ryan P.C. McQuen <0fb25d8cae43e0621b03e40ede14d0668ce2b9a3@linux.com>

shmool/Gisto,Gisto/Gisto,Gisto/Gisto,shmool/Gisto,Gisto/Gisto,shmool/Gisto,Gisto/Gisto