Edited a link in CONTRIBUTING.md (#249)
Edited a link in CONTRIBUTING.md (#249)

The link to "Pseudocode algorithm (pdf)" was pointing to https://github.com/aimacode/pseudocode/blob/master/algorithms.pdf, which was causing the 404 error. The name of the file algorithms.pdf was changed to aima3e-algorithms.pdf by @ctjoreilly in commit 80286be. Edited the link to reflect that change and point to a valid URL.
Chipe1/aima-python,sofmonk/aima-python,Chipe1/aima-python,JoeLaMartina/aima-python,zayneanderson/aima-python,WhittKinley/ConnectProject,abbeymiles/aima-python,aimacode/aima-python,armadill-odyssey/aima-python,austinban/aima-python,austinban/aima-python,SeanCameronConklin/aima-python,chandlercr/aima-python,phaller0513/aima-python,NolanBecker/aima-python,AWPorter/aima-python,JamesDickenson/aima-python,AmberJBlue/aima-python,austinban/aima-python,AmberJBlue/aima-python,SnShine/aima-python,Fruit-Snacks/aima-python,chandlercr/aima-python,willhess/aima-python,WmHHooper/aima-python,WhittKinley/aima-python,abbeymiles/aima-python,SnShine/aima-python,sofmonk/aima-python,willhess/aima-python,WmHHooper/aima-python,SimeonFritz/aima-python,JamesDickenson/aima-python,armadill-odyssey/aima-python,AWPorter/aima-python,jottenlips/aima-python,JoeLaMartina/aima-python,abbeymiles/aima-python,SimeonFritz/aima-python,jo-tez/aima-python,NolanBecker/aima-python,WmHHooper/aima-python,grantvk/aima-python,grantvk/aima-python,reachtarunhere/aima-python,chandlercr/aima-python,grantvk/aima-python,AWPorter/aima-python,phaller0513/aima-python,Fruit-Snacks/aima-python,jo-tez/aima-python,armadill-odyssey/aima-python,aimacode/aima-python,zayneanderson/aima-python,phaller0513/aima-python,JoeLaMartina/AlphametricProject,SeanCameronConklin/aima-python,jottenlips/aima-python,JoeLaMartina/AlphametricProject,NolanBecker/aima-python,zayneanderson/aima-python,JoeLaMartina/aima-python,AmberJBlue/aima-python,willhess/aima-python,jottenlips/aima-python,JoeLaMartina/AlphametricProject,Fruit-Snacks/aima-python,SeanCameronConklin/aima-python,JamesDickenson/aima-python,SimeonFritz/aima-python,WhittKinley/aima-python,WhittKinley/ConnectProject,WhittKinley/aima-python,reachtarunhere/aima-python,WmHHooper/aima-python,WhittKinley/ConnectProject