Remove .md and image files and move python files into main chapter folders

thinkcspy/Chapter-7-Exercises/Problem13.py

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+# Runestone.Academy thinkcspy course
+# Chapter 7
+# Problem 13
+
+def isLeap(year):
+    # your code here
+    if (year % 4 == 0 and year % 100 != 0) or year % 400 == 0:
+        return True
+    else: 
+        return False
+
+def easter(year):
+    a = year % 19
+    b = year % 4
+    c = year % 7
+    d = (19 * a + 24) % 30
+    e = (2 * b + 4 * c + 6 * d + 5) % 7
+        
+    if year >= 1900 and year <= 2099:
+        if isLeap(year):
+            dateofeaster = 22 + d + e - 7
+        else:
+            dateofeaster = 22 + d + e 
+    else:
+        dateofeaster = 0    
+
+    return dateofeaster
+
+def convertDate(year):
+    date = easter(year)
+    
+    if date == 0:
+        print("Error: Date is out of range.")
+    elif date <= 30:
+        print("In", year, "Easter falls on March", date - 1, ".")
+    else:
+        print("In", year, "Easter falls on April", date - 31, ".")
+
+userYear = int(input("Enter a year between 1900 and 2099."))
+
+convertDate(userYear)