cutout/soda: implements PIXEL_i param to cut by pixels on non WCS-standard axis

data-access/engine/src/common/include/ast4vl.hpp

data-access/engine/src/common/include/cutout.hpp

data-access/engine/src/common/include/cutout_nljson.hpp

data-access/engine/src/common/src/cutout.cpp

data-access/engine/src/common/src/cutout_nljson.cpp

data-access/engine/src/common/src/json_region.hpp

data-access/engine/src/vlkb/src/ast.cpp

data-access/engine/src/vlkb/src/main.cpp

data-access/servlet/src/main/java/common/Pixeli.java

...access/servlet/src/main/java/common/json/JsonEncoder.java

data-access/servlet/src/main/java/cutout/Soda.java

data-access/servlet/src/main/java/cutout/SodaImpl.java

...ss/servlet/src/main/java/cutout/webapi/ServletCutout.java

data-access/servlet/src/main/java/mcutout/VlkbCli.java