v0.7.0

Features:

• new rule: no-unassigned-variable
• new rule: no-useless-spread (contributed by @aervin)
• new rule: return-never-call

Bugfixes:

• no-inferred-empty-object: check generic JSX elements (starting from typescript@2.9)
• no-useless-assertion: correctly handle conditional types
• no-useless-predicate: checks comparing typeof with a variable that has a literal type: const str = 'string'; typeof 1 === str;