Removed dead code.
Merge pull request #197 from murrekatt/develop

Removed dead code.
StringUtils: remove str_dup1()
StringUtils: remove len_cmp()
Merge pull request #198 from toxeus/cleanupStringUtils

StringUtils: remove unused functions
opentxs: replace 'false ==' with '!'

Command used:
    sed -i -r 's/( *if \()false == (.*[^\\])$/\1!\2/g' "$file"
Merge pull request #199 from toxeus/cleanupBoolCheck

opentxs: replace 'false ==' with '!'
CMake: add more warning flags
Merge pull request #201 from toxeus/moreWarnings

CMake: add more warning flags
OTAPI_Exec: fix -Wlogical-op

Logical ‘and’ of mutually exclusive tests is always false.
Merge pull request #202 from toxeus/fixLogicalOP

OTAPI_Exec: fix -Wlogical-op
git: improve pre-push hook error message
Merge pull request #204 from toxeus/improveMsg

git: improve pre-push hook error message
Removed some unnecessary includes
opentxs CLI command separation.
Split in one class per command/function.