Split adjoin in two templates
Improve return value construction in adjoin
Merge pull request #2013 from monarchdodra/adjoinBuild

improve adjoin
add std.internal.scopebuffer
Merge pull request #1911 from WalterBright/scopebuffer

add std.internal.scopebuffer
Fix T[] const-ness issue in put
Merge pull request #2016 from monarchdodra/ScopeBufferConst

Fix T[] const-ness issue in put
last_indexOfNone_index

some more

functions created and first unittest

unittests done

documentation

tabs to ws

closing brace by Geod24

some inner function could be made static

none -> neither rename