Lecture 6
added lab6
adding hw2 key
Added lab7 on PCA
Merge branch 'master' of https://github.com/ga-students/DAT_SF_10
Updated syllabus
Updated lec6, added lec7 and papers
added lab7 version 2 with KNN example using PCA
Merge branch 'master' of https://github.com/ga-students/DAT_SF_10
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