fix: comment out 4.5's tabgives and rename 5.0 colors

[rasa]

Just an FYI, nano 3.2 does not report errors using this pre-4.5 PR. I created this and the pre-5.0 PR, as the v2.9 branch is significantly out of date with master per v2.9...master. Also, the name v2.9 doesn't really apply to more recent versions of nano.

If these PRs are accepted, I will submit a PR to update master's readme.md with a note to use these new branches. I will also modify master's install.sh to accept a --branch pre-5.0 parameter.

Using this script, I created the following branches:

1. pre-5.0: changed latte to brightred and purple to brightmagenta.
2. pre-4.5: commented out tabgives
3. pre-2.9.5: changed normal to white, and brightnormal to brightwhite.
4. pre-2.5.3: commented out comment
5. pre-2.3.2: commented out linter
6. pre-2.2.99: commented out magic
7. pre-2.1.5: commented out header, fix regex failures, add quotes around syntax names, and comment out long string causing out of memory error in powershell.nanorc.

This last branch works on MacOS, which has nano version 2.0.6:

$ /usr/bin/nano --version
 GNU nano version 2.0.6 (compiled 17:24:29, Jun  5 2020)
 Email: [email protected]    Web: http://www.nano-editor.org/
 Compiled options: --disable-nls --enable-color --enable-extra --enable-multibuffer --enable-nanorc --enable-utf8

If we include all of these branches, we can close #49, #104, #164, #174, #186, #189, #191, #227, #229, #236, #238, #242, #335 and #349.

[rasa]

Closing in favor of #370