Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56710
Do not perform wrapper mapping if context is being reloaded,
as such mapping is useless and may fail unexpectedly.
Let mapper know that context is being reloaded.

Ignore removeWrapper(), removeWelcomeFile() calls when context is being reloaded,
as that is useless work.
During undeploy the context should have already been unregistered.
During reload the context will be re-registered via addContextVersion().

It is backport of r1610220

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1611472 13f79535-47bb-0310-9956-ffa450edef68
Fix "No context found:" warnings from Mapper.addWrappers() -> findContextVersion() during context startup.
If context has not been started yet, its "AFTER_START" lifecycle event will come later.

It is backport of r1610244

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1611475 13f79535-47bb-0310-9956-ffa450edef68