Use MuseScore instruments in MIDI import

Suitable MuseScore instruments are now collected from instruments.xml (not directly) and set to MIDI tracks.
Search results depend on MIDI program, percussion/not track type, allowed pitch range (aPitchRange) and pitch of percussion instrument. These criteria gives quite small 

A new column (MuseScore instruments) was added to the MIDI import panel which shows a list of available instruments for each track (list also can be not editable in the case of one instrument or empty):
http://wstaw.org/m/2014/12/28/plasma-desktopcr1927.png
http://wstaw.org/m/2014/12/28/plasma-desktopRd1927.png

Now clefs, articulations and so on are set from found instrument templates.
This change fixes several issues, e.g.:
http://musescore.org/en/node/22363
http://musescore.org/en/node/25623
http://musescore.org/en/node/38966