fix defect 4028
add more doc info
add rhels7 stateless and statelite support for x86_64
fix defect #4030 [DEV]'makedhcp -n' failed to add subnet info to dhcpd.conf on rhels7.0 x86_64 mn
updated table rest api description
Merge branch 'master' of ssh://git.code.sf.net/p/xcat/xcat-core

updated table rest api description
add comments for the procedure to handle a restapi request; add comments to describe the definition of URI
add more rest api implementation. refine the doc output
fix autodiscovery problem as not run makehosts command
more code for supporting other hardware in OpenStack baremetal driver.
 fix defect 3981
fix bug #4027, replace chop with chomp
add testcase for makedns
add testcase for makeroutes
add testcase for ppping
add testcase for prsync
add testcase for pscp
add testcase for sysclone
add testcase for xdcp
add testcase for xdsh