[integer] Enhance the comparison operations of BigInt (#60)

This pull request includes significant changes to the `BigInt` and
`BigUInt` benchmarks and arithmetic operations. The changes improve the
initialization and handling of `BigInt` objects, update the benchmarks
to use more descriptive commands, and enhance the comparison operations.
Below are the most important changes:

### Benchmark Improvements:
*
[`benches/bigint/bench.mojo`](diffhunk://#diff-2a97f8dc8465f7a88d361dcee4dcb3020bd75f18a3a189e817fb9af8996bbb75R2):
Added the import for `bench_bigint_multiply` and updated the command
options to use descriptive strings instead of numbers.
[[1]](diffhunk://#diff-2a97f8dc8465f7a88d361dcee4dcb3020bd75f18a3a189e817fb9af8996bbb75R2)
[[2]](diffhunk://#diff-2a97f8dc8465f7a88d361dcee4dcb3020bd75f18a3a189e817fb9af8996bbb75L12-R36)
*
[`benches/biguint/bench.mojo`](diffhunk://#diff-34a58f6f5c1b673b01199db91a3b182f1f345caf0797cbcacadd978e96e4cc10L12-R31):
Updated the command options to use descriptive strings instead of
numbers.

### BigInt Initialization and Arithmetic Enhancements:
*
[`src/decimojo/bigint/arithmetics.mojo`](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL54-R57):
Replaced the `empty` and `capacity` parameters with `List[UInt32]` for
initializing `BigInt` objects in various arithmetic functions.
[[1]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL54-R57)
[[2]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL120-R121)
[[3]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL227-R228)
[[4]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL346-R358)
[[5]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL393-R393)
[[6]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL419-R419)
[[7]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL431-R431)
[[8]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL484-R484)
[[9]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL505-R505)
[[10]](diffhunk://#diff-1ffcd7baf2074053c5e9680efda5d243ac5a3096ebf39049f4670a48bc0a932fL523-R523)

### BigInt Struct Enhancements:
*
[`src/decimojo/bigint/bigint.mojo`](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL76-R128):
Deprecated the `empty` and `capacity` parameters in `BigInt`
initialization, introduced new constructors for safer initialization
from lists and words, and added comparison dunders (`__gt__`, `__ge__`,
`__lt__`, `__le__`, `__eq__`, `__ne__`).
[[1]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL76-R128)
[[2]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bR183-R202)
[[3]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL179-R218)
[[4]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL189-R239)
[[5]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL208-R260)
[[6]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL236-R277)
[[7]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL262-R301)
[[8]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bR472-R506)
[[9]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bR518-R524)
[[10]](diffhunk://#diff-d65a756a58e3387a2b30bbe88308c3b318d71d2116b2870ac0a44109729e554bL495-R575)

### Comparison Module Update:
*
[`src/decimojo/bigint/comparison.mojo`](diffhunk://#diff-d7e30fa4bdf75c4935df70d55fd5fe8b02a9530e5a3f012fe61958a0b82311ccL21-R22):
Removed unnecessary import and added the import for `BigUInt`.

Author: forfudan

benches/bigint/bench.mojo

@@ -1,4 +1,5 @@
 from bench_bigint_add import main as bench_add
+from bench_bigint_multiply import main as bench_multiply
 from bench_bigint_truncate_divide import main as bench_truncate_divide
 from bench_bigint_floor_divide import main as bench_floor_divide
 
@@ -9,26 +10,30 @@ fn main() raises:
 =========================================
 This is the BigInt Benchmarks
 =========================================
-1:       Add
-2:       Truncate Divide
-3:       Floor Divide
-4:       Run all benchmarks
-5:       Exit
+add:         Add
+mul:         Multiply
+trunc:       Truncate divide
+floor:       Floor divide (//)
+all:         Run all benchmarks
+q:           Exit
 =========================================
 """
     )
     var command = input("Type the number of the bench you want to run: ")
-    if command == "1":
+    if command == "add":
         bench_add()
-    elif command == "2":
+    elif command == "mul":
+        bench_multiply()
+    elif command == "trunc":
         bench_truncate_divide()
-    elif command == "3":
+    elif command == "floor":
         bench_floor_divide()
-    elif command == "4":
+    elif command == "all":
         bench_add()
+        bench_multiply()
         bench_truncate_divide()
         bench_floor_divide()
-    elif command == "5":
+    elif command == "q":
         return
     else:
         print("Invalid input")