HW4: regex guide submission

@Liniarc and I's completed regular expression guide.

init commit
Thomas's Line
added regex program files
added mouse support and support for extended regex
made backend changes
first section
added some of literal and metacharacters info
formatting fixes
formatting testing
really sorry, I can't get formatting to work
eventually this formatting will look right
formatting this way is easier
formatting better work
hope this makes it not look bad
formatting
but more importantly using GitHub's editor
added abilities to check solutions and have multiple problems
updated formatting
added problems
updated code to work with matching problems
removed test file
major formatting and content update
includes table of contents and resources
formatting and posix specific changes
added content and posix specific information
moved brackets
Added backrefs
Updated a bunch of things' formatting
Updated rest of things' formatting
Minor edit to README
Fixed compiling issues on hammer machine
changed problem 10
Added a replace example
Minor edit to README
moved files around
added README for program
added links
Echoing to grep for clarity in the Readme
Update README.md
Update README.md
added link to regex practice program
formatting fixes
Moved program to its own repository