Spelling errors in contributing.md (krzjoa#29)

Spelling error in 'position' Line 5

Author: Agrover112

CONTRIBUTING.md

@@ -2,7 +2,7 @@
 If you came here, I suppose you would like to add a lib this list. To do it well, you should follow these rules.
 
 1. Take a critical look: is the proposed lib really awesome?
-2. If does, add this lib in the relevant section at the last positionn. Bear in mind, that in many cases one library may fit multiple categories. Choose exactly one, to not duplicate contents.
+2. If does, add this lib in the relevant section at the last position. Bear in mind, that in many cases one library may fit multiple categories. Choose exactly one, to not duplicate contents.
 3. Obviously, check if the library does not occur in the list!
 4. Adorn with coresponding icon(s) if possible (such as sklearn, TensorFlow and so on).
 5. Description should start with a capital letter and be ended with proper punctuation.