fix: -rh ""

[arthur4ires]

Python Error:

[+] Sending token
Traceback (most recent call last):
  File "/jwt_tool/jwt_tool.py", line 2034, in <module>
    rejigToken(headDict, paylDict, sig)
  File "/jwt_tool/jwt_tool.py", line 1330, in rejigToken
    jwtOut(newContents+"."+sig, "Sending token")
  File "/jwt_tool/jwt_tool.py", line 232, in jwtOut
    resData = sendToken(token, cookiedict, logID, headertoken[0], posttoken[0])
  File "/jwt_tool/jwt_tool.py", line 144, in sendToken
    headerName, headerVal = eachHeader.split(":",1)
ValueError: not enough values to unpack (expected 2, got 1)

When -rh is equal to "" the script tries to do a split and ends up giving an error.

I added a condition to check this.