add 'notbuilt' to list of job colors

Getting this error when listing an upbuilt job:

Traceback (most recent call last):
File "C:\Teamcity\BuildAgent2\work\3676ab95343f4f4e\env\Scripts\ajk-list-script.py", line 9, in <module>
load_entry_point('autojenkins==0.9.0', 'console_scripts', 'ajk-list')()
File "C:\Teamcity\BuildAgent2\work\3676ab95343f4f4e\env\lib\site-packages\autojenkins\run.py", line 200, in list
list_jobs(host, options, not options.color, options.raw)
File "C:\Teamcity\BuildAgent2\work\3676ab95343f4f4e\env\lib\site-packages\autojenkins\run.py", line 130, in list_jobs
out = COLOR_MEANING[color][position]
KeyError: 'notbuilt'
[14:09:03][Step 1/1] Process exited with code 1
Merge pull request #19 from dgholz/master

add 'notbuilt' to list of job colors