Integrated Open Graph tags, added custom remote_api logic and fixed bugs

app.yaml
	-Removed remote_api built-in
	-added (commented out) url handler for custom remote_api url
	-set home page to use secure protocol

bootstrap/css/
	-updated Bootstrap with custom version (no mobile support)

css/main.css
	-ensures that the layout stops shrinking after viewport width goes lower than 1240px

css/skilltree.css
	-added rules for a new moduleBox highlight

home.py, openid_login.py, skill_tree.py
	-added url and host arguments to the jinja2 templates

templates/
	-home, login and skill tree pages now have Open Graph and Twitter Card meta tags, complete with URL generation via jinja2

remote_api.py
	-custom remote_api hack to allow access even when OpenID is enabled
	-insecure, therefore should be disabled via app.yaml when not needed.

scripts/script.js
	-share URL no longer contains the hex symbol
	-singular pre-requisites are no longer added automatically, instead they'll be given the prerequisite group treatment
	-notification text altered when a singular prerequisite is removed.
	-disabled default behaviour when semester dropdown items are clicked

scripts/skillTree.js
	-prereqGroups are also Droppable
	-moduleBoxes now gain a class when draggables are hovered on top of them
	-prereqGroups no longer display the moduleInfo panel
Prevented scraper from parsing preclusions for bridging modules