piff-ams – Early macros for us­ing AMS fonts

This pack­age was cre­ated (in its present form) af­ter the ad­vent of LaTeX 2e, but be­fore the cor­re­spond­ing macros from the AMS it­self had ar­rived. Those macros are now part of the stan­dard LaTeX dis­tri­bu­tion as part of AMS-LaTeX.