Добавлены post-запросы, реализован сервер для первого РК
 Запуск по URL localhost:8080/main
 В ветке master:
  Изменения для закрепления:
	new file:   .idea/uiDesigner.xml
	new file:   server_tml/admin.tml
	new file:   server_tml/login.html
	new file:   server_tml/main.html
	new file:   server_tml/sign_up.html
	new file:   src/main/java/frontend/AdminPageServlet.java
	new file:   src/main/java/frontend/LogOutServlet.java
	new file:   src/main/java/frontend/MainPageServlet.java
	new file:   src/main/java/frontend/SignInServlet.java
	new file:   src/main/java/frontend/SignUpServlet.java
	new file:   src/main/java/frontend/TimeHelper.java
	modified:   src/main/java/main/AccountService.java
	modified:   src/main/java/main/Main.java
	modified:   src/main/java/main/UserProfile.java
	new file:   target/classes/frontend/AdminPageServlet.class
	new file:   target/classes/frontend/LogOutServlet.class
	new file:   target/classes/frontend/MainPageServlet.class
	new file:   target/classes/frontend/SignInServlet.class
	new file:   target/classes/frontend/SignUpServlet.class
	new file:   target/classes/frontend/TimeHelper.class
	new file:   target/classes/main/AccountService.class
	modified:   target/classes/main/Main.class
	new file:   target/classes/main/UserProfile.class