[mybuild] Initial import.
[mybuild] Initial checkin.
[mybuild] Add few tests using python's built-in unittest module
[mybuild] Add few negative test cases, an insignificant change in Optuple._to_expr()
[mybuild] Move some constrain logic out from the internal dict.
Also add Constraints.freeze() method to catch possible bugs when using forking.
[mybuild] insignificant changes in unit tests
[mybuild] Add a simple test case for Constraints.
[mybuild] Docstrings for exceptions
[mybuild] Almostly move out constraints-related logic from ConstraintsDict.
[mybuild] Rename and move ConstraintsDict up to the module level.
[mybuild] Making Module type independent from the rest types (Instance, etc.)
[mybuild] Extract Context-related classes into a separate module.
[mybuild] Move Instance class from core package to context.
[mybuild] Extract Constraints into a separate module, fix few imports.
[mybuild] Nothing significant: add missing and remove unused imports, etc.
[mybuild] Extract constraints test into a separate file.
[mybuild] Improve test for Constraints, fix a little bug in the latter.
[mybuild] Assert pureness of certain operations on Constraints.
[mybuild] Working on option definition facilities.
[mybuild] Integrating Options class into Optuple and ModuleContext
(incomplete, code is in a broken state)