add lectures 26, 27, 28

...win/26_Files_and_Directories/26_Files_and_Directories.pdf

...in/26_Files_and_Directories/26_Files_and_Directories.pptx

...s/Lecture Code/Lec26_Files_and_Directories_Solution.ipynb

...s/Lecture Code/Lec26_Files_and_Directories_Template.ipynb

...win/27_Pandas-1/Lecture Code/Lec27_Pandas1_Solution.ipynb

...win/27_Pandas-1/Lecture Code/Lec27_Pandas1_Template.ipynb

s24/AmFam_Ashwin/27_Pandas-1/Lecture Code/pokemon_stats.csv

s24/AmFam_Ashwin/28_Pandas-2/Lec_28_Pandas2_Worksheet.ipynb

...AmFam_Ashwin/28_Pandas-2/Lecture Code/IMDB-Movie-Data.csv

...win/28_Pandas-2/Lecture Code/Lec28_Pandas2_Solution.ipynb

...win/28_Pandas-2/Lecture Code/Lec28_Pandas2_Template.ipynb

s24/AmFam_Ashwin/28_Pandas-2/lec-28-worksheet.pdf

s24/AmFam_Ashwin/28_Pandas-2/storms.csv