v0.6.1 [Important Fixes!]

Features:

• A simple limit system for submissions (a7b94a6)
• Upgrade go-sqlite and sqlite (07d35e3)
• Fix concurrent SQLite connections messing up the write queries (692cda1) by @minhducsun2002 !

Bugfixes:

• Small front-end fixes (dd1377e)
• New "Contributors" link (fcd2ab2) by @ngkan !

Misc:

• Add contributing information (2e3d84b)