Added JInstruction#to_binary and JInstruction#to_hex methods
Added instruction base class used by all instruction types
Update readme
Fuss with readme format some more
Make Instruction constructor private
Rework tests to get sample add tokens from helper
Change from private constructor to exception raising constructor to allow subclass instantiation
Added jump token generation to helper
Added jump to sample lines
Added #to_binary test for jump
Fixed instruction#to_hex
added Assembler#to_binary_string to create binary string of arbitrary size
Added j-type codes
Added all fields to j_instruction Constructor
Changed order of JInstruction#new arguments
Fixed Assembler#convert_binary test expected result
Removed debug print statements
Added #convert_hex test for jump
Separated #convert_hex and #convert_binary tests by instruction type
added get_jal_tokens and get_loadi_tokens to spec helper