Rename config items

- host -> hostname
- column -> testname

see: http://hobbit.math.cnrs.fr/hobbit/help/manpages/man1/bb.1.html
Remove dead code
Add custom determine color feature support

set ruby code of determinate color to config_param :custom_determine_color_code

Parameter
----

time, record, value

Example
----

everytime 'green'

````
custom_determine_color_code return 'green'
````

if value > 90 then 'red'
else 'green'

````
custom_determine_color_code if  value > 90; 'red'; else 'green'; end
````

If raise some exception
----

use config color value and write warn log
gem version++
Eval custom_determine_color_code when configure
Refactoring spec
Edit README.md
Merge pull request #1 from bash0C7/namahamu

mege v0.0.1 -> master