feat: add Template create, update, and delete methods [DX-900] [DX-901] [DX-902]#2969

Michael Pham (michaelphamcf) wants to merge 4 commits intofeat/dx-898-899-template-getmany-getcontentful/contentful-management.js:feat/dx-898-899-template-getmany-getfrom

feat/dx-900-901-902-template-create-update-deletecontentful/contentful-management.js:feat/dx-900-901-902-template-create-update-deleteCopy head branch name to clipboard