Add note about adhering to SemVer
Add note about adhering to SemVer

Closes #213
czeeb/keep-a-changelog,ginovva320/keep-a-changelog,czeeb/keep-a-changelog,suhyunjeon/keep-a-changelog,vmlinz/keep-a-changelog,cogmission/keep-a-changelog,cogmission/keep-a-changelog,metavida/keep-a-changelog,ginovva320/keep-a-changelog,tianshuo/keep-a-changelog,bstroebl/keep-a-changelog,assispedro/keep-a-changelog,tianshuo/keep-a-changelog,skarekrow/keep-a-changelog,hunan-rostomyan/keep-a-changelog,suhyunjeon/keep-a-changelog,hunan-rostomyan/keep-a-changelog,vmlinz/keep-a-changelog,skarekrow/keep-a-changelog,tianshuo/keep-a-changelog,bstroebl/keep-a-changelog,assispedro/keep-a-changelog,metavida/keep-a-changelog