Support for .pro INI files (KiCad project files)

Update the heuristic for .pro to include both INI and QMake files
Fixes #2116

samples/INI/MouseKeyboard.pro

@@ -0,0 +1,71 @@
+update=Sun 15 Feb 2015 01:10:10 PM EST
+last_client=eeschema
+[pcbnew]
+version=1
+PageLayoutDescrFile=
+LastNetListRead=
+UseCmpFile=1
+PadDrill=0.6
+PadDrillOvalY=0.6
+PadSizeH=1.5
+PadSizeV=1.5
+PcbTextSizeV=1.5
+PcbTextSizeH=1.5
+PcbTextThickness=0.3
+ModuleTextSizeV=1
+ModuleTextSizeH=1
+ModuleTextSizeThickness=0.15
+SolderMaskClearance=0
+SolderMaskMinWidth=0
+DrawSegmentWidth=0.2
+BoardOutlineThickness=0.09999999999999999
+ModuleOutlineThickness=0.15
+[pcbnew/libraries]
+LibDir=
+[general]
+version=1
+[eeschema]
+version=1
+PageLayoutDescrFile=
+SubpartIdSeparator=0
+SubpartFirstId=65
+LibDir=/home/hschmale/KiCad/LibMods-3rdParty
+NetFmtName=
+RptD_X=0
+RptD_Y=100
+RptLab=1
+LabSize=60
+[eeschema/libraries]
+LibName1=power
+LibName2=device
+LibName3=transistors
+LibName4=conn
+LibName5=linear
+LibName6=regul
+LibName7=74xx
+LibName8=cmos4000
+LibName9=adc-dac
+LibName10=memory
+LibName11=xilinx
+LibName12=special
+LibName13=microcontrollers
+LibName14=dsp
+LibName15=microchip
+LibName16=analog_switches
+LibName17=motorola
+LibName18=texas
+LibName19=intel
+LibName20=audio
+LibName21=interface
+LibName22=digital-audio
+LibName23=philips
+LibName24=display
+LibName25=cypress
+LibName26=siliconi
+LibName27=opto
+LibName28=atmel
+LibName29=contrib
+LibName30=valves
+LibName31=arduino_shieldsNCL
+LibName32=con-usb-2
+LibName33=2axispotwselect