[syntax_highlight] Fix deprecation warnings, fix pylint errors

This fixes some deprecation warnings related to Gtk.Color and restructures
code and formatting according to pylint suggestions

syntax_highlight/types.py

@@ -1,21 +1,24 @@
-from enum import Enum, IntEnum, unique
+from enum import Enum
+from enum import IntEnum
+from enum import unique
+
+PLUGIN_INTERNAL_NONE_LEXER_ID = '_syntax_highlight_internal_none_type'
 
-PLUGIN_INTERNAL_NONE_LEXER_ID='_syntax_highlight_internal_none_type'
 
 class MatchType(Enum):
-    INLINE      = 0
-    MULTILINE   = 1
-    TEXT        = 2
+    INLINE = 0
+    MULTILINE = 1
+    TEXT = 2
+
 
 @unique
 class LineBreakOptions(IntEnum):
-    NEVER       = 0
-    ALWAYS      = 1
-    MULTILINE   = 2
+    NEVER = 0
+    ALWAYS = 1
+    MULTILINE = 2
+
 
 @unique
 class CodeMarkerOptions(IntEnum):
-    AS_COMMENT  = 0
-    HIDE        = 1
-
-
+    AS_COMMENT = 0
+    HIDE = 1