Add preliminary colorful diff output support

Very crude implementation, but is supposed to work on most terminals.
Make the user osc plugins directory has higher priority

IMHO, this is a common sense.
Add geturl command (alpha)

To better integrate with build service's web site.
geturl(beta): most functionalities are implemented.
Add link package revision

also remove "Page" from output, it's quite a excess.
Fix color display for added and deleted lines

to be like the output of git diff, switch colors

added: green
deleted: red
Add color to "geturl" output
- updated NEWS file (preparation for the upcoming 0.145 release)
- prepare 0.145.0 release
- open 0.146 development
Support .kiwi files for bash-completion

This commit enables osc to provide completion for both .spec and .kiwi
files, and ensures no ugly "not found" messages are displayed in the
terminal due to globbing.
- get "osc build --prefer-pkgs ..." working with Arch
Merge branch 'master' of https://github.com/ikeydoherty/osc
Make rdelete/undelete work without args in a working copy
support maintenance release request with acceptinfo data (OBS 2.6)
- fixed testsuite (and indention)

Broken by commit 0e3641610eb25e72a7ecf8abeaa82398dc3c88e2
- do_submitrequest: use continue to start next loop iteration (instead of "next"...)
support installonly/noinstall tags for mock buildengine
- handle ImportError of a plugin more gracefully

See bnc#876538 for the details.
- do_maintainer: fixed typo (that cause a TypeError)