Merge various prs

[GitGitro]

Hi! i've merged various pull requests in order to bring the project a bit up to date and fix some bugs

all credits are in the commits as i have cherry-picked but here are the authors:
@azumukupoe
@uuupah
@diogosena
@D3viantS4ge
@ryansereno

this fixes:
#131 #32 #74 #64 #65 #38 #25 #24

[diogosena]

Please include this commit diogosena@d3eea11

[D3viantS4ge]

Perhaps the delimiter should be configurable via --md-artistdelimiter?

[thegreatestgiant]

@GitGitro I used your version and whenever it comes across a song that I already have in my playlist, it downloads it again but adds a _1

###   SKIPPING: Panic! At The Disco - Girls _ Girls _ Boys (SONG ALREADY EXISTS)   ###

Panic! At The Disco - Girls _ Girls _ Boys: 100%|████████████████████████████████████████████████████████████████▉| 3.52M/3.53M [00:21<00:00, 169kB/s]
                                                                                                                                                      ###   Downloaded "Panic! At The Disco - Girls _ Girls _ Boys" to "Creative title/Panic! At The Disco - Girls _ Girls _ Boys_1.ogg" in 21s (plus 5s converting)   ###

                                                                                                                                                      
###   SKIPPING: Panic! At The Disco - The Ballad of Mona Lisa (SONG ALREADY EXISTS)   ###

Panic! At The Disco - The Ballad of Mona Lisa: 100%|█████████████████████████████████████████████████████████████▉| 3.92M/3.92M [00:26<00:00, 156kB/s]
                                                                                                                                                      ###   Downloaded "Panic! At The Disco - The Ballad of Mona Lisa" to "Creative title/Panic! At The Disco - The Ballad of Mona Lisa_1.ogg" in 26s (plus 3s converting)   ###