Add latex base commands (mostly class stuff)

[yitzchak]

• [x] CheckCommand
• [x] Error/Warning/Info
• [x] ProvidesClass, etc
• [x] ExecuteOptions,
• [x] NeedsTeXFormat,
• [x] PassOptionsToClass, etc.
• [x] ProcessOptions
• [x] cline
• [x] discretionary
• [x] enlargethispage
• [x] footnote
• [x] footnotemark
• [x] footnotetext
• [x] hyphenation
• [x] linebreak
• [x] nolinebreak
• [x] pagebreak
• [x] nopagebreak
• [x] newcounter
• [x] newfont
• [x] newlength
• [x] newsavebox
• [x] printcounter
• [x] setcounter
• [x] stepcounter
• [x] value
• [x] settodepth
• [x] settoheight
• [x] settowidth
• [x] protect
• [x] pagenumbering
• [x] pagestyle
• [x] hspace, vspace
• [x] addvspace
• [x] raisebox
• [x] sbox, savebox
• [x] usebox
• [x] lrbox