Change abbreviation guideline

[Keboo]

Currently we have separate rules for abbreviations and acronyms. This proposal brings those together into single rules. The existing rules do not match which what most code does with well-known abbreviations such as: ID (Identifier), Company abbreviations, DB (Database), TM (Trademark), Cert (Certificate), Sig (Signature), etc.

Proposal: Change the following guidelines:

❌ DO NOT use abbreviations or contractions within identifier names.
❌ DO NOT use any acronyms unless they are widely accepted, and even then use them consistently.
✔️ DO capitalize both characters in two-character acronyms, except for the first word of a camelCased identifier.
✔️ DO capitalize only the first character in acronyms with three or more characters, except for the first word of a camelCased identifier.
❌ DO NOT capitalize any of the characters in acronyms at the beginning of a camelCased identifier.

To be:

❌ DO NOT use contractions within identifier names.
⛔ AVOID use any acronyms or abbreviations unless they are widely accepted, and even then, use them consistently.
✔️ DO capitalize only the first character in acronyms or abbreviations with two or more characters, except for the first word of a camelCased identifier.
❌ DO NOT capitalize any of the characters in acronyms or abbreviations at the beginning of a camelCased identifier.

[joeriddles]

I approve after discussion with @Keboo and @adamskt 👍

[Keboo]

@joeriddles @adamskt After discussion with @MarkMichaelis there is a suggestion to change the severity of the second rule to a DO NOT

So:
❌ DO NOT use contractions within identifier names.
⛔ AVOID use any acronyms or abbreviations unless they are widely accepted, and even then, use them consistently.
❌ DO NOT use any acronyms or abbreviations unless they are widely accepted, and even then, use them consistently.
✔️ DO capitalize only the first character in acronyms or abbreviations with two or more characters, except for the first word of a camelCased identifier.
❌ DO NOT capitalize any of the characters in acronyms or abbreviations at the beginning of a camelCased identifier.

The rational for this change is there should be no exceptions where an acronym or abbreviation is used that is not widely accepted. Or to put it another way, in general things should be spelled out, and if an abbreviation is to be used, the case must be made that it is widely accepted.

[joeriddles]

LGTM.