Add a microcode assembler. A microcode "program" is a series of statements. Each...

Add a microcode assembler. A microcode "program" is a series of statements. Each statement has an optional label at the beginning, a capitilized microcode class name which is roughly equivalent to a mnemonic in a regular ISA, and then an optional series of operands seperated by white space. The operands are either a decimal constant, a label, or a code fragment surrounded by non nested {}s. Labels are a letter or underscore followed by letters, underscores, or digits. The syntax for describing code segments might need to be changed if a need arrises to have {}s in the code itself.

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extra : convert_revision : 8e5cfdd1a3c9a7e3731fdf6acd615ee82ac2b9b7