mac: fix build issue with qmake

support for pkg-config is disabled by default in the Qt package for mac.
  this will turn it on
remove duplicated lines of code
implement update_action and change the context menu's upload to update
rename not_update to use_upload
Merge pull request #300 from haiwen/patch-30-fix-qmake-build-with-macports

mac: fix build issue with qmake
Merge pull request #301 from haiwen/patch-31-remove-duplicate-lines

remove duplicated lines of code
several improvements
add support for cmake-xcode build
fix a typo
fixed set_repo_property rpc call
remove three trivial lines
Merge pull request #294 from haiwen/patch-27-implement-update-action

implement update_action and change the context menu's upload to update
apply several fixes including rename operation fix

rename operation returns a 301 which causes a mistake in some platforms

QString::right returns a substring n rightmost characters of the string, not the
substring starting from n.

don't use objects after calling deleteLater, which is kind of dangerouse (and causing
segment fault easily)
Merge pull request #305 from haiwen/fix-set-repo-property-rpc

fixed set_repo_property rpc call
update version to 4.0.1
Merge pull request #303 from haiwen/feature-xcode

add support for cmake-xcode build
Merge pull request #306 from haiwen/fix-rename-operation

apply several fixes including rename operation fix
don't force a refresh after successful upload or update request
implement the missing oid part
expire the dirent_cache after successful upload/update request