Only require colorama on Windows (#266)

Co-authored-by: K.B.Dharun Krishna <[email protected]>

Author: hukkin

Diff for: requirements.txt

@@ -1,3 +1,3 @@
 termcolor
-colorama
+colorama; sys_platform=='win32'
 shtab>=1.3.10

Diff for: tldr.py

@@ -15,7 +15,6 @@
 from urllib.request import urlopen, Request
 from urllib.error import HTTPError, URLError
 from termcolor import colored
-import colorama  # Required for Windows
 import shtab
 
 __version__ = "3.3.0"
@@ -643,6 +642,7 @@ def main() -> None:
     parser = create_parser()
 
     options = parser.parse_args()
+
     display_option_length = "long"
     if not (options.short_options or options.long_options):
         if os.environ.get('TLDR_OPTIONS') == "short":
@@ -657,7 +657,10 @@ def main() -> None:
         display_option_length = "long"
     if options.short_options and options.long_options:
         display_option_length = "both"
-    colorama.init(strip=options.color)
+    if sys.platform == "win32":
+        import colorama
+        colorama.init(strip=options.color)
+
     if options.color is False:
         os.environ["FORCE_COLOR"] = "true"