Create a .pdf user manual

[leahvschaffer]

*Guides user through each module
*Explains purpose of each module
*Explains what each button/parameter does

[acesnik]

Good note! Here's a user manual outline. Feel free to gut it or adapt it. https://github.com/smith-chem-wisc/ProteoformSuite/tree/master/ProteoformSuiteManual