20190505 QSSTV 9.4.1

• redesign of the template editor
• fixed template image corruption when image Fit mode was selected.
• use of transparent images fixed (imageBackgroundColor (see Config GUI) is used to process transparency)
• removed c++11 Config option in qsstv.pro. Eliminated dependencies on c++11 to commpile with older compilers.

• complete rewrite of the FTP interfaces. They now run in a seperate thread
• removed Hybrid notify config. All hybrid configurations are in one tab: Hybrid size of recorded wav files was internally set to 0, fixed.
• tx audio to wav file was output in mono with half the samples -> fixed
• scaling of images in sstv tx mode -> fixed
• show image with template when loading new image ->fixed
• callsign was not set/send in DRM tx
• new FFT implementation
• compression in DRM now based on size in stead of ratio
• fix error in reedsolomon decode when no erasures found
• repeater functions implemented
• fixed bug in AVT24-AVT90-AVT94
• removed use VIS option in SSTV (now when a VIS code is detected, the mode is restricted to that VIS mode)
• added confirmation options for delete files and program exit in gui configuration
• more testing on raspberry Pi 3 model B. (compilation and execution OK)
• added PKTLSB, PKTUSB and PKTFM in frequency config modulation
• added passband to frequency settings
• minor bug fixes