test: enable -bigobj option for MSVC compiler

Fixes C1128 compiler error raised for some test binaries
due to exceeded limit of addressable sections

Add tests for various corner cases

fix make_persistent_atomic

string: add assign methods

fix rethrowing constructor exception

tests: change function name to match behaviour

add vector range() and crange() methods

Run tests on tmpfs on travis

fix string's methods description

Improve code coverage for locking APIs and transactions.

test: add gnome-terminal support

string: add compare functions

Bump pmdk to 1.5.1 in Docker images.

Throw an exception when unlocking failed.

Limit test execution time on AppVeyor.

test: rm vector_private test

vector: add comparison operators between pmem::vector and std::vector

add .gitattributes