[FLOSS] Renaming Tasks

[mwoelfer-tuwien]

The following renaming/refactoring tasks currently exist:

• remove options from ksLookup
  • Move functionality of ksLookup(..., KDB_O_POP) to a new function ksRemoveKey #3979
  • [FLOSS H1] remove KDB_O_CREATE #4034
  • KDB_O_DEL should be removed
  • All other options should not be used outside src/libs/elektra/keyset.c
  • The elektraLookupFlags options argument of ksLookup should be removed. The implementation of ksLookup should be moved to a new static ksLookupInternal that keeps the argument.
• Replace keyGetMeta/keySetMeta by keyMeta+ksLookupByName/ksAppendKey
  • All uses of keyGetMeta/keySetMeta must be changed to always use the meta:/ namespace prefix
  • replace keySetMeta and keyGetMeta with static inline function #3980
• Replace keyGetName/keyGetString/keyGetBinary by keyName/keyString/keyValue+memcpy (or similar)
  • Remove functions copying into a buffer #3975