[Linux] os-release: unescape quotes / backslashes
The os-release specification states that single quotes, double quotes
and backslashes are supposed to be escaped with \. Unfortunately
I missed this in my original commit 7a9aa6f5d9ac8df1c79eb06ed63bce8af162c3ba.

http://www.freedesktop.org/software/systemd/man/os-release.html
Expose ACTION_FOO, ICON_TYPE_FOO and KEY_CODE_FOO to addons
avoid attempting mac-discovery for internet addresses
Don't display blank SMB workgroups.
FIX: avoid waiting forever on a locked CPluginDirectory while exiting
FIX: Consistenly look for fonts in special//home, then special://xbmc
Sort buttons depend directly on available sort methods
Implement seek for CDDA
Python: Add a DelayedCallGuard to xbmc.executeJSONRPC.

Avoids locking other python threads running on the same process space as XBMC, since executeJSONRPC may trigger activity on them.
FIX: [stagefright] ignore frames with no valid pts
[Fix] Event server code for remote mouse with event client protocol
fix #3166: use URIUtils::AddFileToFolder
SysInfo: add "GetBuildTargetCpuFamily" function
Added JSONRPC.NotifyAll as a built-in function
SysInfo: add "GetXbmcBitness" function
SysInfo: refactoring IsOS64bit->GetKernelBitness, extend support for all platforms
Startup log: write information about target CPU; XBMC and OS bitness
Startup log: report number of CPU cores
Settings: remove unused setting
Faster sorting of CFileItemLists, step 1

CFileItemLists are sorted by first construcing a SortItems object that refers
back to each CFileItem by index, sorting the SortItems object, then rebuilding
CSortItemList::m_items (a vector of pointers to CFileItems) by examination of
the sorted version of the SortItems object.

It might be more sensible, long-term, to sort m_items directly, but in the
meantime, there are a couple of simple ways to make sorting with SortItems
sufficiently efficient that it's not a problem any more.

Previously, SortItems was a vector of SortItem objects, held by value; each
SortItem was a std::map (implemented as a red-black tree) which ended up
being constructed and destructed as each element of SortItems was moved.
This patch changes SortItems to be a vector of pointers to SortItems instead.

Benchmarks for CFileItemList::Sort() on a Raspberry Pi with a library of
600 movies:
Before patch: 4.6 seconds
After patch:  1.1 seconds