Change for automatical download video with this same duration as spotify song (#111)

* Changes in .gitignore file:
 - added .python-version
This file is used in pyenv to select good python version.

Changes in core/misc.py:
 - added function get_sec to convert HH:mm:ss to seconds

Changes in spotdl.py:
 - in function generate_songname
     change function to receive generate_metadata, this is optymalization, becouse in oldest version metadata from spotify api is downlaoded 2 times
 - in function generate_youtube_url
     song variable use changed function generate_songname
     function now looking for songs in while, and save data to dict. Dictionary is used in manual and auto mode. In dictionary keep is youtube link, title, videotime (in format HH:mm:ss) and videotime converted to seconds.
     For now in automatic downloading is selected video with least difference betwen youtube video time and time from spotify. This is important, becouse in youtube a lot of movies has scenes before/after without musics.

* Fix parameter in generate_songname() and dual calls

* Fix tests

* Skip tests that depend on the location (for the moment)

* Remove unnecessary code

core/misc.py

@@ -118,3 +118,15 @@ def filter_path(path):
 def grace_quit():
     print('\n\nExiting.')
     sys.exit()
+    
+def get_sec(time_str):
+   v = time_str.split(':', 3)
+   v.reverse()
+   sec = 0
+   if len(v) > 0: #seconds
+       sec += int(v[0])
+   if len(v) > 1: # minutes
+       sec += int(v[1]) * 60
+   if len(v) > 2: # hours
+       sec += int(v[2]) * 3600
+   return sec