Lecture 6
added lab6
Merge branch 'master' of https://github.com/ga-students/DAT_SF_10

Conflicts:
	Labs/Lab3/DAT10-lab03.ipynb
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
Updatin the stuffs
Merge branch 'master' of https://github.com/ga-students/DAT_SF_10
HW3 (lab 6) added