Updated 'Commit guidelines' section and added 'Reviewing and merging' one
Updated 'Commit guidelines' section and added 'Reviewing and merging' one

tdziurko/jvm-bloggers,jvm-bloggers/jvm-bloggers,tdziurko/jvm-bloggers,kraluk/jvm-bloggers,szpak/jvm-bloggers,szpak/jvm-bloggers,szpak/jvm-bloggers,szpak/jvm-bloggers,sobkowiak/jvm-bloggers,tdziurko/jvm-bloggers,kraluk/jvm-bloggers,kraluk/jvm-bloggers,jvm-bloggers/jvm-bloggers,kraluk/jvm-bloggers,jvm-bloggers/jvm-bloggers,sobkowiak/jvm-bloggers,tdziurko/jvm-bloggers,jvm-bloggers/jvm-bloggers