workaround for error caused by bug in latest meteor version

in Accounts.ui a new extraSignupFields setting was introduced.
There's a bug where if it's not set, an error gets thrown.
Here we set it to an emtpy array to stop the error.:
ensure we require pagedown-boostrap v0.0.3
remove unused showdown to prevent marked helper name conflict
code tidy
code tidy
restore old CtoA message
Merge branch 'master' of github.com:solvers/solvers
fix broken package link
tweak project header
Merge branch 'better-404-fix' of github.com:davedx/solvers into davedx-better-404-fix

Conflicts:
	app/client/templates/projects/showProject.html
	app/packages/.gitignore
	app/packages/marked
	app/server/projects.js
fix GA for project ids, tags and users