There are no simple alphabet commands

[Yarakashi-Kikohshi]

The following three commands are missing simple alphabetic commands.

• \Planckconst (⇔ \mith)
• \Im (⇔ \mfrakI)
• \Re (⇔ \mfrakR)

Of course, I know that we can express these using \symit{...} and \symfrak{...}, however, just as \hslash has the alias \hbar, I think these characters should be given aliases \mith, \mfrakI and \mfrakR.