Rename Project Euler directories and other dependent changes (#3300)

* Rename all Project Euler directories:

Reason:
The change was done to maintain consistency throughout the directory
and to keep all directories in sorted order.

Due to the above change, some config files had to be modified:
'problem_22` -> `problem_022`

* Update scripts to pad zeroes in PE directories

project_euler/problem_019/sol1.py

@@ -0,0 +1,64 @@
+"""
+Counting Sundays
+Problem 19
+
+You are given the following information, but you may prefer to do some research
+for yourself.
+
+1 Jan 1900 was a Monday.
+Thirty days has September,
+April, June and November.
+All the rest have thirty-one,
+Saving February alone,
+Which has twenty-eight, rain or shine.
+And on leap years, twenty-nine.
+
+A leap year occurs on any year evenly divisible by 4, but not on a century
+unless it is divisible by 400.
+
+How many Sundays fell on the first of the month during the twentieth century
+(1 Jan 1901 to 31 Dec 2000)?
+"""
+
+
+def solution():
+    """Returns the number of mondays that fall on the first of the month during
+    the twentieth century (1 Jan 1901 to 31 Dec 2000)?
+
+    >>> solution()
+    171
+    """
+    days_per_month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+
+    day = 6
+    month = 1
+    year = 1901
+
+    sundays = 0
+
+    while year < 2001:
+        day += 7
+
+        if (year % 4 == 0 and not year % 100 == 0) or (year % 400 == 0):
+            if day > days_per_month[month - 1] and month != 2:
+                month += 1
+                day = day - days_per_month[month - 2]
+            elif day > 29 and month == 2:
+                month += 1
+                day = day - 29
+        else:
+            if day > days_per_month[month - 1]:
+                month += 1
+                day = day - days_per_month[month - 2]
+
+        if month > 12:
+            year += 1
+            month = 1
+
+        if year < 2001 and day == 1:
+            sundays += 1
+    return sundays
+
+
+if __name__ == "__main__":
+    print(solution())