Gitignore file has been improved.
Merge pull request #672 from maximkhatskevich/master

Gitignore file has been improved.
deletion of ending characters made easier
Fixed type conversion
Fixed build of mailcore2 for iOS 7.1
Made very short display string even shorter
Fixed a warning
Updated travis scripts
Install CMake before building
Added missing linker flags on doc for Mac
Fixed IMAP disconnect cancellation
Fixed crash when no sender is set (fixed #699)
Fixed thread safety in certificate check (fixed #670)
Turn off TidyMark to clean up HTML output
Merge pull request #702 from gnachman/tidyMarkOff

Turn off TidyMark to clean up HTML output
Added message flags mask