Update for v0.0.10 release

[ulyssa]

I am preparing for the v0.0.10 release in ulyssa/iamb#333, and will need to make sure the website is updated to document:

• Support marking a room as a direct message room iamb#92
• Add external_edit_file_suffix to config iamb#253
• Allow typing newline with <S-Enter> and enable keyboard enhancement protocol iamb#272 (there should be a list of supported terminals)
• Implement set/unset/show for alternative and canonical aliases iamb#279
• Fix openSUSE link and installation command in README iamb#283
• Add command to set per-room notification levels iamb#305
• Add message slash commands iamb#317
• Support reacting literally with non-Emojis iamb#320
• Add metadata for cargo-deb and cargo-generate-rpm iamb#321 (mention something under source install?)
• Build cross-platform binaries and packages of main iamb#323 (mention something near release "GitHub Release")
• Add ban/unban/kick room commands iamb#327
• Add command for setting room history visibility iamb#328
• Add commands for viewing and clearing unreads iamb#332