initial commit of debug additions

added debugging to dhcpd() class

added argument for dhcp debugging to server.py
added better debugging verbosity
update documentation

updated documentation for dhcpd() debug mode
updated docs

minor modification
updated docs

added default value of `—dhcp-debug`
Merge branch 'dhcpd-debug'
updated docs

reflect status of overall debugging
made changes based on psychomario's commits

updated todo

made changed to dhcpd.py
Merge branch 'dhcpd-debug'
assigned self to debug modes

updated TODO.md
manual merge for #24
typo
str -> repr