add basic completion support for fish shell
fish shell completion: help arguments
Initialize variable 's_built' during image build.

Fixed images local build failure because of
uninitialized variable 's_built'.
- support new history including review history of OBS 2.6
 - display request priorities, if important or critical
 - add "osc rq priorize" command to re-priorize existing requests
 - allow also "osc rq ls" shortcut
- roll 0.148 release for new request history support
- fix description rendering in history elements
- fix crash with not existing priorities
- do_createrequest: remove --diff option

This never worked and makes no sense (IMHO): use "osc request" for things
like that.
- fixed #113 ("osc creq -s ...")
Fix condition for using urllib2 workaround

See https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=762825
- fixed #99 ("do_package_tracking = 0")
fix osc service exit code

Commands like "osc service disabledrun" would always return exitcode 0
even when the source service failed.  This broke any scripts which
wrapped around osc service.
- do not hardcode path to the build scripts and removed legacy check
- support multiple parallel maintenance workflows

for the same projects. So do not use project "maintains", but the
attribute to be able to switch between maintenance, security and PTF
working contexts for example.
- oops, fixed typo

Call "update_needed" instead of "needs_update"
- raise more specific exceptions
- prepare 0.149 bugfix release
- open 0.150 development
- do_addremove: use local variable instead of an attribute (cosmetic)