savesym – Redefine symbols where names conflict

There are a number of symbols (e.g., \Square) that are defined by several packages. In order to typeset all the variants in a document, we have to give the glyph a unique name. To do that, we define \savesymbol{XXX}, which renames a symbol from \XXX to \origXXX, and \restoresymbols{yyy}{XXX}, which renames \origXXX back to \XXX and defines a new command, \yyyXXX, which corresponds to the most recently loaded version of \XXX.