Modularize structure to add support for new styles and different input files

[nitrocode]

Summary

• Allows any number of markdown files (so you can add resume.md and cover.md to generate pdfs for both)
• Moved resume.md to markdown/resume.md
• Moved style_* styles/chmduquesne.*
• Added variables to Makefile to easily swap in a style, input directory, and output directory
• Created output directory as the first command when running make all or any make commands

This should allow us to add new styles easily (#2)

Before running make all

➜  pandoc_resume_clean git:(modularize-structure) tree
.
├── docker-compose.yml
├── LICENSE
├── Makefile
├── markdown
│   └── resume.md
├── README.md
└── styles
    ├── chmduquesne.css
    └── chmduquesne.tex

2 directories, 7 files

After running make all

➜  pandoc_resume_clean git:(modularize-structure) tree
.
├── docker-compose.yml
├── LICENSE
├── Makefile
├── markdown
│   └── resume.md
├── output
│   ├── context_resume.log
│   ├── resume.docx
│   ├── resume.html
│   ├── resume.log
│   ├── resume.pdf
│   ├── resume.rtf
│   ├── resume.tex
│   └── resume.tuc
├── README.md
└── styles
    ├── chmduquesne.css
    └── chmduquesne.tex

3 directories, 15 files

@mszep One last PR and I'll take a break :)

[nitrocode]

@mszep 😄

[mszep]

Awesome! Thanks so much, and sorry for the delay in getting back to you!

[nitrocode]

No worries at all, thanks for merging!