Finish subcommand revamping

[whisperity]

Subcommands in the new layout

(✓ means that the thing has been merged.)

• log New subcommand infrastructure + splitting out log command #610
• analyze New user commands for analysis #639
• parse New user commands for analysis #639
• store New user commands for analysis #639
• check (wrapper) New user commands for analysis #639
• quickcheck (wrapper) New user commands for analysis #639
• plist (wrapper) New user commands for analysis #639
• analyzers Add analyzer listing and detail view #629
• checkers Refurbished checker listing and detail view  #634
• server Move viewer server to new structure #655
• cmd Move cmd command to its own handler #666
• debug Move 'debug' command to new structure #656
• version Move version command to new structure #657

Also:

• Subcommands should go into a subfolder of libcodechecker, not directly into the main dir. Put subcommands to package under libcodechecker #707
• Better output for available subcommands in installer. Subcommand cleanup and fixing user guide #706

Various other TO-DO

• Clang Static Analyzer and Clang-Tidy should be links in the README.md. Subcommand cleanup and fixing user guide #706
• Clean-up and fix docs/user_guide.md. Subcommand cleanup and fixing user guide #706

[whisperity]

@gyorb Will do this tomorrow too. I thought this would go out in 5.8, sorry that my semester dragged on so long.

[gyorb]

@whisperity no problem we will finish it in 5.9