Use O_CLOEXEC for files that remain open for extended time

Tell the OS we're not interested in keeping these open across exec()
calls. This may help prevent running out of resources when calling a
function like system() which doesn't close everything. And it looks
to be good practice anyway.
PluginBrowser: Introduce instant plugin manual re-order

In the pluginbrowser you are now able to re-order plugins via the < > buttons instantly
PluginBrowser: When ordered allow appearing new plugins

Once oredered with the previous plugin new plugins were not showed. Now they will appear at the bottom
PluginBrowser: Corrigate move behaviour when moving around start en end

Then a simple swap does not do the job for us.
In addition customize the order is only usefull when we have more than one plugin
MovieSelection: allow binding directories to buttons

Actions that begin with a "/" are expected to be directories to jump
to. Now only to find a nicer way to assign these in the GUI than browsing
through a randomly sorted list.
epgcache.cpp: Allow other (Python) threads to run during text search

While searching for text, release the GIL so that other Python threads
get a chance to run. Doesn't really matter much, it just looks neat.
This is less simple for the next step, because that part manipulates
Python objects.
epgcache: Use std::dequeue instead of c array for descriptor list

Instead of trashing the stack with a 2k fixed-size array, simply
allocate it on the heap. A dequeue fits well here, because we only
use it sequentially, and it has faster insertion than a vector.

We have a C++ compiler and libraries, so let's use them.
Merge branch 'master' of git://git.code.sf.net/p/openpli/enigma2