Refine Diagnostic Filters and adds human-readable diagnostic names

[markwpearce]

Addresses #1060

• Changes the structure of bsconfig.json "diagnosticFilters" option to look like this:

Array<string | number | { files?: string | Array<string | { src: string } | { dest: string }>; codes?: Array<number | string> }>;

In more detail:

{
"diagnosticFilters": [
    123,   // numbers are applied to diagnostic code or legacyCode against all files
    "some-diagnostic-name", // strings are applied to diagnostic code (or legacyCode) against all files
    { "codes": ["code-1", "code-2"]}, // an object is allowed with a list of codes to applied against all files
    { "files": "some/glob/**" }, // a file list will suppress all diagnostics in matched files
    { "files": "other/glob/**", "codes": ["some-code"]}, //suppress specific codes in matched files
    { "files": [              //files can be an array of globs
            "other/glob/**",
            "other2/glob/**"
       ],
       "codes": ["some-code"]
    },
    { "files": [{ "src": "yet/another/glob/**"}] }, //file listings in an array can be a object that references src path
    { "files": [{ "dest": "yet/another/glob/**"}] } //file listings in an array can be a object that references dest path
]}

Additionally, I went through all the diagnostics and assigned a human-readable code property to them, which can also be used for any diagnostic filtering. The previous (numerical) code property was renamed to legacyCode

[markwpearce]

@josephjunker Please take a look at this PR -- you did a lot of work on DiagnosticFiltering and I hope that's respected here.

[josephjunker]

@markwpearce Looks good to me!

[TwitchBronBron]

I did an initial pass of this and have some suggestions. I still need to go through every diagnostic code and tweak their names, that'll come later.

[TwitchBronBron]

We've only made it through diagnostic code 1063. Figure I'll submit what I have awhile, and keep working.

[TwitchBronBron]

Suggested change

	code: 'expected-expression-for-each'
	code: 'missing-loop-expression'

Some devs may struggle undrestanding what expression means, perhpas mixing it up with binaryExpression from for loop. Is there a better name?

[TwitchBronBron]

Suggested change

	code: 'unexpected-colon-before-if'
	code: 'unexpected-leading-colon'

We can expand this messaging/diagnostic in the future to more things that do this.

[TwitchBronBron]

Suggested change

	code: 'expected-terminator-on-then'
	code: 'missing-if-terminator'

Let's consider merging all "missing terminator" into a single diagnostic. Something like missing-statement-terminator. That would aply to namespaces, enums, classes, constants, if statements, etc etc. Then parameterize the message so each message makes sense.

Several of the if statement diagnostics below would also apply.

[markwpearce]

I like this idea.

[TwitchBronBron]

Maybe merge a few of these together, parameterize the message a bit.