docs: Fix many man page style issues

• docs: Fix grypo
• docs: Fix groff warnings in ps(1)
• docs: Fix style warnings in man pages
• docs: Drop no-op calls of deprecated PD macro
• docs: Make "EXIT STATUS" sections consistent
• docs: Restyle tagged paragraph sequence (1/5)
• docs: Restyle tagged paragraph sequence (2/5)
• docs: Restyle tagged paragraph sequence (3/5)
• docs: Restyle tagged paragraph sequence (4/5)
• docs: Restyle tagged paragraph sequence (5/5)
• docs: Stop shouting "Unix" in full capitals
• docs: Fix misuse of UR/UE macros
• docs: Fix bug report address formatting in free(1)
• docs: Set lists more economically
• docs: Fix vertical spacing problems (1/2)
• docs: Fix vertical spacing problems (2/2)
• docs: Revise "STANDARD FORMAT SPECIFIERS" table
• docs: Drop superfluous PP macros before SH
• docs: Migrate to idiot-proof quotation marks
• docs: Use idiomatic ellipsis markup
• docs: Make command synopses idiomatic, consistent