Extract common parts from jhbuildrc files.
https://bugs.webkit.org/show_bug.cgi?id=125986

Patch by Peter Szanka <h868064@stud.u-szeged.hu> on 2014-02-06
Reviewed by Csaba Osztrogonác.

* efl/common.py: Removed.
* efl/jhbuildrc:
* gtk/common.py:
(binary_build_path):
* gtk/find-make-dist-errors:
(get_missing_headers):
* gtk/generate-gtkdoc:
(get_webkit2_options):
(get_webkit1_options.src_path):
(get_webkit1_options):
(get_webkitdom_options.src_path):
(get_webkitdom_options):
* gtk/generate-inspector-gresource-manifest.py:
* gtk/jhbuildrc:
* jhbuild/jhbuildrc_common.py: Added.
(script_path):
(top_level_path):
(init):
* nix/common.py: Removed.
* nix/jhbuildrc:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@163530 268f45cc-cd09-0410-ab3c-d52691b4dbfc