Question: I'm new to C++ and am wondering how much time I should invest in learning how to implement template classes. Are they widely used in industry, or is this something I should move through quickly?

Answer: 
You'll need them sooner or later ;) But for a beginner they are a bit tricky to write (but easy to use, so use STL intensively). And after mastering other c++ skills (const-correctness, operators overloading, learning about compilation units etc) and gaining some experience you will start coding templates for yourself. So my advice: use them but learn how to write them when you'll find you need them. It will be much quicker and effective learning if you gain some experience with standard c++ constructs first.
Of course they are used in the industry. Just look at the Standard Template Library (STL)!

You definitely should know how to work with templates, and better, learn how to do some fancy things with them like template metaprogramming, ok, that may be optional, but template classes are not!

**EDIT:** Even more, a lot of other languages like Java and C# support the concept of generics, that being the equivalent to templates in c++, but generics are far more restrictive.