Fix typo
Update .travis files to have consistent site/build names
Fix .travis files

- OSX sed expects parameter for "-i" option
- for Windows and OSX build, we need to get the commit hash of HEAD~
  instead of HEAD because we made an extra commit to trigger the build
Parse decimal values

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
Add 'Variables' command.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
Move 'slow' test files to different subdir. Modify CTestCustom.cmake.in to run leantests.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>