Replace the function names in listed files

[Seyi007]

          [R/pre-msa-tree.R](https://github.com/JRaviLab/MolEvolvR/blob/main/R/pre-msa-tree.R)

R/CHANGED-pre-msa-tree.R

Original	Modified	User Facing
RepresentativeAccNums	createRepresentativeAccessionNumbers
write.MsaAAMultipleAlignment	writeMsaAaMultipleAlignment2FA
get_accnums_from_fasta_file	getAccessionNumbersFromFA

R/reverse_operons.R

Original	Modified	User Facing
reveql	straightenOperonSeq
reverse_operon	reverseOperonSeq

Originally posted by @the-mayer in #7 (comment)

All updates should follow this format:

Original	Modified	User Facing
original_function	newFunction	✅

NOTE: Before beginning to work on a particular file, please check to see that @jananiravi has given the 👍 on the comment.

Please follow the contributing guidelines and create a new branch containing your changes. Commit your work, and submit a PR when ready for review.

Additionally, use the search in all files functionality in VS code, Rstudio, or any other text editor, and list all files the function is being called or used to be updated later.

[jananiravi]

These need to be renamed from the original list #7, as well. E.g., AccessionNumbers to AccNum. MSA -- all caps, etc.

[teddyCodex]

These need to be renamed from the original list #7, as well. E.g., AccessionNumbers to AccNum. MSA -- all caps, etc.

Hi @jananiravi this name writeMSAAAMultipleAlignment2FA doesn't seem very intuitive especially cos of the 'AAA'
Any suggestions for a better name?
cc @the-mayer
does writeMSA_AAMultipleAlignment2FA work?

[jananiravi]

writeMSA_AA2FA should, in fact, suffice, I think. [could you double-check to see that's what the function does?]
cc: @epbrenner