fixes #151, bump python version, mimic human typing behavior

[iamtalhaasghar]

I have done some minor but very useful improvements:

• bump python to version 3.7
• created requirements.txt file
• mimic human typing behavior to avoid ban related to Number got banned after 5 messages #136
• return True or False boolean value depending on msg sent status success / failure so that client program can handle situation accordingly related to New function to ensure message is successfully sent #127
• find_user returns True if account exists otherwise False
• fixes issues:
  TypeError: WebDriver.__init__() got multiple values for argument 'options #151
  Unable to use the library #144
  TypeError: WebDriver.__init__() got multiple values for argument 'options' #142
  Unable to start #139
  There is no such driver Issue #133
  TypeError: __init__() got multiple values for argument 'options' #126

[sgaechter]

I'd love to see this pull request added to the project.