Support for Step counts in greater than 4 bytes (HOTP) and support for custom time interval (TOTP)

Made some very small changes to the code in order to support step counts greater than 4 bytes (aka in the range of 'long' instead of 'int') and added a constructor for using a custom time interval for clients that don't use 30 seconds as their password window.

Just as a warning, in order to get the code to compile quickly on my machine I changed the project files to remove the dependencies on semver and other things. Sorry for that :S