Improve test coverage, fix several bugs

[patricksurry]

• fix #91
• fix #113
• fix bugs in order and m*/
• adds tests for at-xy, page, order, see, dump, disasm, .s, ?, words, bell, block-c65-init

I simplified the capture/restore output routine from ed.fs and moved to tester.fs so I could use elsewhere. The basic pattern is T{ capture-output some-word restore-output ( addr n ) ... }T.
The compare-masked routine is a bit brittle for comparing, e.g. see output where address lengths can change. I might replace with a super basic compare-glob to handle that at some point.

I also changedtalitest-c65.py to provide an empty blockfile so we can test the c65 block i/o.

[SamCoVT]

This looks good. Having the output for things like see will mean those tests will have to be updated if we change the format, but it should help us catch if we change something accidentally.