More icon fixes

* Octicon info button looks aweful compared to fa... so switching
* Doc tweak on grammar
* Add missing info button to repo list page
* Correct icon for add library in the user tools panel
* Improve code tag breaking when viewport is super small on add script/lib page ... `word-break: break-all;` doesn't appear to work this round with scaling... but leaving in for the time being.
* Apply same rule for #342 line breaking ... again doesn't appear to work this round of testing but should.
* Add icons to comment popup
* Add icon to user tools
* Add icon to Danger Zone
* Add icons to Admin section
* Add icons to source code editor save button... retro here with the diskette ;) Flip to using button tag instead of input tag.
* Add icon to edit profile
* Add icon to edit script info
* Match text in new script page for forking
* Fix trash can icon in delete script
* Add icon in delete script
* Add fa-fw class to general reply button (the blue one) for symmetry on all buttons save for the md editor which doesn't have this one for preview by default
* Add fa-fw class to new issue and correct from info to success for symmetry

There's probably more but this should be the bulk of them.

Applies to #186