Remove bare exceptions

[girotobial]

The codebase is littered with bare exceptions.

try:
    foo()
except:
    something_else()

At best this is preventing keyboard and system exits. At worst it is masking a lot of bugs. They should be replaced with a named exception type, or at the very least Exception.

I.e

try:
    foo()
except ValueError:
    something_else()

or

try:
    foo()
except Exception:
    something_else()