added support for Android logcat
refactored AssertLevel and AssertAction enums
published PEMPEK_STATIC_ASSERT
renamed PEMPEK_ASSERT_CONCATENATE helper to PEMPEK_ASSERT_JOIN
removed '#define VC_EXTRALEAN' as it only make sense for MFC projects
updated README's TLDR section
renamed 'PEMPEK_' to 'PPK_' to improve concision and adoption
fixed typo in README.md
updated .gitignore
replaced seekp(0) by flush() in README

because VC++ sets the failbit when seeking to the beginning of an empty
stringstream
force -Wformat into error around PPK_ASSERT calls when compiling with GCC 4.6+ and Clang

the error is only generated for PPK_ASSERT, not the rest of the code
fixed Debug and Warning assertion inversion, introduced by commit:0c4bad6