close #21

Mostly replaced Fixnum with integer
also in the rx-file dependency
all travis and testing with 2.4+

lib/arm/attributed.rb

@@ -19,7 +19,7 @@ module Arm
 
     # for the shift handling that makes the arm so unique
     def shift val , by
-      raise "Not integer #{val}:#{val.class} #{inspect}" unless val.is_a? Fixnum
+      raise "Not integer #{val}:#{val.class} #{inspect}" unless val.is_a? ::Integer
       val << by
     end
 

lib/arm/constants.rb

@@ -63,7 +63,7 @@ module Arm
       if r_name.is_a? ::Risc::RegisterValue
         r_name = r_name.symbol
       end
-      if r_name.is_a? Fixnum
+      if r_name.is_a? ::Integer
         r_name = "r#{r_name}"
       end
       r = REGISTERS[r_name.to_s]

lib/arm/instructions/compare_instruction.rb

@@ -5,7 +5,7 @@ module Arm
       super(nil)
       @attributes = attributes
       @left = left
-      @right = right.is_a?(Fixnum) ? IntegerConstant.new(right) : right
+      @right = right.is_a?(::Integer) ? IntegerConstant.new(right) : right
       @attributes[:condition_code] = :al if @attributes[:condition_code] == nil
       @operand = 0
       @attributes[:update_status] = 1