OP-1571 added placeholder directories and whats_this.txt files.
OP-1571 Fixed template export.

User can now choose a place and a name if preferred.
Location will be default location in GCS config dir if it exists,
otherwise in the users home directory.
Added code to handle exort and import/selection of template without
image.
OP-1570 Wrong defaults mixing for default airframe (QuadX)
OP-1572 Fix regression, missed QuadH added
OP-1572 Regression introduced with QuadH frame added
Merge branch 'laurent/OP-1570_Default_QuadX_mix_values' into rel-14.10
Merge branch 'thread/OP-1571_Cloud_Enhancements' into rel-14.10